src/Doc/JEdit/JEdit.thy
author wenzelm
Sat Nov 24 18:56:44 2018 +0100 (5 months ago)
changeset 69343 395c4fb15ea2
parent 68737 a8bef9ff7dc0
child 69597 ff784d5a5bfb
permissions -rw-r--r--
use "Isabelle DejaVu" fonts uniformly: Text Area, GUI elements, HTML output etc.;
     1 (*:maxLineLen=78:*)
     2 
     3 theory JEdit
     4 imports Base
     5 begin
     6 
     7 chapter \<open>Introduction\<close>
     8 
     9 section \<open>Concepts and terminology\<close>
    10 
    11 text \<open>
    12   Isabelle/jEdit is a Prover IDE that integrates \<^emph>\<open>parallel proof checking\<close>
    13   @{cite "Wenzel:2009" and "Wenzel:2013:ITP"} with \<^emph>\<open>asynchronous user
    14   interaction\<close> @{cite "Wenzel:2010" and "Wenzel:2012:UITP-EPTCS" and
    15   "Wenzel:2014:ITP-PIDE" and "Wenzel:2014:UITP"}, based on a document-oriented
    16   approach to \<^emph>\<open>continuous proof processing\<close> @{cite "Wenzel:2011:CICM" and
    17   "Wenzel:2012"}. Many concepts and system components are fit together in
    18   order to make this work. The main building blocks are as follows.
    19 
    20     \<^descr>[Isabelle/ML] is the implementation and extension language of Isabelle,
    21     see also @{cite "isabelle-implementation"}. It is integrated into the
    22     logical context of Isabelle/Isar and allows to manipulate logical entities
    23     directly. Arbitrary add-on tools may be implemented for object-logics such
    24     as Isabelle/HOL.
    25 
    26     \<^descr>[Isabelle/Scala] is the system programming language of Isabelle. It
    27     extends the pure logical environment of Isabelle/ML towards the outer
    28     world of graphical user interfaces, text editors, IDE frameworks, web
    29     services, SSH servers, SQL databases etc. Special infrastructure allows to
    30     transfer algebraic datatypes and formatted text easily between ML and
    31     Scala, using asynchronous protocol commands.
    32 
    33     \<^descr>[PIDE] is a general framework for Prover IDEs based on Isabelle/Scala. It
    34     is built around a concept of parallel and asynchronous document
    35     processing, which is supported natively by the parallel proof engine that
    36     is implemented in Isabelle/ML. The traditional prover command loop is
    37     given up; instead there is direct support for editing of source text, with
    38     rich formal markup for GUI rendering.
    39 
    40     \<^descr>[jEdit] is a sophisticated text editor\<^footnote>\<open>\<^url>\<open>http://www.jedit.org\<close>\<close>
    41     implemented in Java\<^footnote>\<open>\<^url>\<open>https://www.java.com\<close>\<close>. It is easily extensible by
    42     plugins written in any language that works on the JVM. In the context of
    43     Isabelle this is always Scala\<^footnote>\<open>\<^url>\<open>https://www.scala-lang.org\<close>\<close>.
    44 
    45     \<^descr>[Isabelle/jEdit] is the main application of the PIDE framework and the
    46     default user-interface for Isabelle. It targets both beginners and
    47     experts. Technically, Isabelle/jEdit consists of the original jEdit code
    48     base with minimal patches and a special plugin for Isabelle. This is
    49     integrated as a desktop application for the main operating system
    50     families: Linux, Windows, Mac OS X.
    51 
    52   End-users of Isabelle download and run a standalone application that exposes
    53   jEdit as a text editor on the surface. Thus there is occasionally a tendency
    54   to apply the name ``jEdit'' to any of the Isabelle Prover IDE aspects,
    55   without proper differentiation. When discussing these PIDE building blocks
    56   in public forums, mailing lists, or even scientific publications, it is
    57   particularly important to distinguish Isabelle/ML versus Standard ML,
    58   Isabelle/Scala versus Scala, Isabelle/jEdit versus jEdit.
    59 \<close>
    60 
    61 
    62 section \<open>The Isabelle/jEdit Prover IDE\<close>
    63 
    64 text \<open>
    65   \begin{figure}[!htb]
    66   \begin{center}
    67   \includegraphics[scale=0.333]{isabelle-jedit}
    68   \end{center}
    69   \caption{The Isabelle/jEdit Prover IDE}
    70   \label{fig:isabelle-jedit}
    71   \end{figure}
    72 
    73   Isabelle/jEdit (\figref{fig:isabelle-jedit}) consists of some plugins for
    74   the jEdit text editor, while preserving its general look-and-feel as far as
    75   possible. The main plugin is called ``Isabelle'' and has its own menu
    76   \<^emph>\<open>Plugins~/ Isabelle\<close> with access to several actions and add-on panels (see
    77   also \secref{sec:dockables}), as well as \<^emph>\<open>Plugins~/ Plugin Options~/
    78   Isabelle\<close> (see also \secref{sec:options}).
    79 
    80   The options allow to specify a logic session name, but the same selector is
    81   also accessible in the \<^emph>\<open>Theories\<close> panel (\secref{sec:theories}). After
    82   startup of the Isabelle plugin, the selected logic session image is provided
    83   automatically by the Isabelle build tool @{cite "isabelle-system"}: if it is
    84   absent or outdated wrt.\ its sources, the build process updates it within
    85   the running text editor. Prover IDE functionality is fully activated after
    86   successful termination of the build process. A failure may require changing
    87   some options and restart of the Isabelle plugin or application. Changing the
    88   logic session, or the underlying ML system platform (32\,bit versus 64\,bit)
    89   requires a restart of the whole application to take effect.
    90 
    91   \<^medskip>
    92   The main job of the Prover IDE is to manage sources and their changes,
    93   taking the logical structure as a formal document into account (see also
    94   \secref{sec:document-model}). The editor and the prover are connected
    95   asynchronously in a lock-free manner. The prover is free to organize the
    96   checking of the formal text in parallel on multiple cores, and provides
    97   feedback via markup, which is rendered in the editor via colors, boxes,
    98   squiggly underlines, hyperlinks, popup windows, icons, clickable output etc.
    99 
   100   Using the mouse together with the modifier key \<^verbatim>\<open>CONTROL\<close> (Linux, Windows)
   101   or \<^verbatim>\<open>COMMAND\<close> (Mac OS X) exposes formal content via tooltips and/or
   102   hyperlinks (see also \secref{sec:tooltips-hyperlinks}). Output (in popups
   103   etc.) may be explored recursively, using the same techniques as in the
   104   editor source buffer.
   105 
   106   Thus the Prover IDE gives an impression of direct access to formal content
   107   of the prover within the editor, but in reality only certain aspects are
   108   exposed, according to the possibilities of the prover and its add-on tools.
   109 \<close>
   110 
   111 
   112 subsection \<open>Documentation\<close>
   113 
   114 text \<open>
   115   The \<^emph>\<open>Documentation\<close> panel of Isabelle/jEdit provides access to some example
   116   theory files and the standard Isabelle documentation. PDF files are opened
   117   by regular desktop operations of the underlying platform. The section
   118   ``Original jEdit Documentation'' contains the original \<^emph>\<open>User's Guide\<close> of
   119   this sophisticated text editor. The same is accessible via the \<^verbatim>\<open>Help\<close> menu
   120   or \<^verbatim>\<open>F1\<close> keyboard shortcut, using the built-in HTML viewer of Java/Swing.
   121   The latter also includes \<^emph>\<open>Frequently Asked Questions\<close> and documentation of
   122   individual plugins.
   123 
   124   Most of the information about jEdit is relevant for Isabelle/jEdit as well,
   125   but users need to keep in mind that defaults sometimes differ, and the
   126   official jEdit documentation does not know about the Isabelle plugin with
   127   its support for continuous checking of formal source text: jEdit is a plain
   128   text editor, but Isabelle/jEdit is a Prover IDE.
   129 \<close>
   130 
   131 
   132 subsection \<open>Plugins\<close>
   133 
   134 text \<open>
   135   The \<^emph>\<open>Plugin Manager\<close> of jEdit allows to augment editor functionality by JVM
   136   modules (jars) that are provided by the central plugin repository, which is
   137   accessible via various mirror sites.
   138 
   139   Connecting to the plugin server-infrastructure of the jEdit project allows
   140   to update bundled plugins or to add further functionality. This needs to be
   141   done with the usual care for such an open bazaar of contributions. Arbitrary
   142   combinations of add-on features are apt to cause problems. It is advisable
   143   to start with the default configuration of Isabelle/jEdit and develop some
   144   sense how it is meant to work, before loading too many other plugins.
   145 
   146   \<^medskip>
   147   The \<^emph>\<open>Isabelle\<close> plugin is responsible for the main Prover IDE functionality
   148   of Isabelle/jEdit: it manages the prover session in the background. A few
   149   additional plugins are bundled with Isabelle/jEdit for convenience or out of
   150   necessity, notably \<^emph>\<open>Console\<close> with its \<^emph>\<open>Scala\<close> sub-plugin
   151   (\secref{sec:scala-console}) and \<^emph>\<open>SideKick\<close> with some Isabelle-specific
   152   parsers for document tree structure (\secref{sec:sidekick}). The
   153   \<^emph>\<open>Navigator\<close> plugin is particularly important for hyperlinks within the
   154   formal document-model (\secref{sec:tooltips-hyperlinks}). Further plugins
   155   (e.g.\ \<^emph>\<open>ErrorList\<close>, \<^emph>\<open>Code2HTML\<close>) are included to saturate the dependencies
   156   of bundled plugins, but have no particular use in Isabelle/jEdit.
   157 \<close>
   158 
   159 
   160 subsection \<open>Options \label{sec:options}\<close>
   161 
   162 text \<open>
   163   Both jEdit and Isabelle have distinctive management of persistent options.
   164 
   165   Regular jEdit options are accessible via the dialogs \<^emph>\<open>Utilities~/ Global
   166   Options\<close> or \<^emph>\<open>Plugins~/ Plugin Options\<close>, with a second chance to flip the
   167   two within the central options dialog. Changes are stored in @{path
   168   "$JEDIT_SETTINGS/properties"} and @{path "$JEDIT_SETTINGS/keymaps"}.
   169 
   170   Isabelle system options are managed by Isabelle/Scala and changes are stored
   171   in @{path "$ISABELLE_HOME_USER/etc/preferences"}, independently of
   172   other jEdit properties. See also @{cite "isabelle-system"}, especially the
   173   coverage of sessions and command-line tools like @{tool build} or @{tool
   174   options}.
   175 
   176   Those Isabelle options that are declared as \<^verbatim>\<open>public\<close> are configurable in
   177   Isabelle/jEdit via \<^emph>\<open>Plugin Options~/ Isabelle~/ General\<close>. Moreover, there
   178   are various options for rendering document content, which are configurable
   179   via \<^emph>\<open>Plugin Options~/ Isabelle~/ Rendering\<close>. Thus \<^emph>\<open>Plugin Options~/
   180   Isabelle\<close> in jEdit provides a view on a subset of Isabelle system options.
   181   Note that some of these options affect general parameters that are relevant
   182   outside Isabelle/jEdit as well, e.g.\ @{system_option threads} or
   183   @{system_option parallel_proofs} for the Isabelle build tool @{cite
   184   "isabelle-system"}, but it is possible to use the settings variable
   185   @{setting ISABELLE_BUILD_OPTIONS} to change defaults for batch builds
   186   without affecting the Prover IDE.
   187 
   188   The jEdit action @{action_def isabelle.options} opens the options dialog for
   189   the Isabelle plugin; it can be mapped to editor GUI elements as usual.
   190 
   191   \<^medskip>
   192   Options are usually loaded on startup and saved on shutdown of
   193   Isabelle/jEdit. Editing the generated @{path "$JEDIT_SETTINGS/properties"}
   194   or @{path "$ISABELLE_HOME_USER/etc/preferences"} manually while the
   195   application is running may cause surprise due to lost updates!
   196 \<close>
   197 
   198 
   199 subsection \<open>Keymaps\<close>
   200 
   201 text \<open>
   202   Keyboard shortcuts are managed as a separate concept of \<^emph>\<open>keymap\<close> that is
   203   configurable via \<^emph>\<open>Global Options~/ Shortcuts\<close>. The \<^verbatim>\<open>imported\<close> keymap is
   204   derived from the initial environment of properties that is available at the
   205   first start of the editor; afterwards the keymap file takes precedence and
   206   is no longer affected by change of default properties.
   207 
   208   Users may change their keymap later, but this may lead to conflicts with
   209   \<^verbatim>\<open>shortcut\<close> properties in \<^file>\<open>$JEDIT_HOME/src/jEdit.props\<close>.
   210 
   211   The action @{action_def "isabelle.keymap-merge"} helps to resolve pending
   212   Isabelle keymap changes that are in conflict with the current jEdit keymap;
   213   while non-conflicting changes are applied implicitly. This action is
   214   automatically invoked on Isabelle/jEdit startup.
   215 \<close>
   216 
   217 
   218 section \<open>Command-line invocation \label{sec:command-line}\<close>
   219 
   220 text \<open>
   221   Isabelle/jEdit is normally invoked as a single-instance desktop application,
   222   based on platform-specific executables for Linux, Windows, Mac OS X.
   223 
   224   It is also possible to invoke the Prover IDE on the command-line, with some
   225   extra options and environment settings. The command-line usage of @{tool_def
   226   jedit} is as follows:
   227   @{verbatim [display]
   228 \<open>Usage: isabelle jedit [OPTIONS] [FILES ...]
   229 
   230   Options are:
   231     -A NAME      ancestor session for options -R and -S (default: parent)
   232     -D NAME=X    set JVM system property
   233     -J OPTION    add JVM runtime option
   234                  (default $JEDIT_JAVA_SYSTEM_OPTIONS $JEDIT_JAVA_OPTIONS)
   235     -R NAME      build image with requirements from other sessions
   236     -S NAME      like option -R, with focus on selected session
   237     -b           build only
   238     -d DIR       include session directory
   239     -f           fresh build
   240     -i NAME      include session in name-space of theories
   241     -j OPTION    add jEdit runtime option
   242                  (default $JEDIT_OPTIONS)
   243     -l NAME      logic image name
   244     -m MODE      add print mode for output
   245     -n           no build of session image on startup
   246     -p CMD       ML process command prefix (process policy)
   247     -s           system build mode for session image
   248 
   249   Start jEdit with Isabelle plugin setup and open FILES
   250   (default "$USER_HOME/Scratch.thy" or ":" for empty buffer).\<close>}
   251 
   252   The \<^verbatim>\<open>-l\<close> option specifies the session name of the logic image to be used
   253   for proof processing. Additional session root directories may be included
   254   via option \<^verbatim>\<open>-d\<close> to augment the session name space (see also @{cite
   255   "isabelle-system"}). By default, the specified image is checked and built on
   256   demand. The \<^verbatim>\<open>-s\<close> option determines where to store the result session image
   257   of @{tool build}. The \<^verbatim>\<open>-n\<close> option bypasses the implicit build process for
   258   the selected session image.
   259 
   260   The \<^verbatim>\<open>-R\<close> option builds an auxiliary logic image with all theories from
   261   other sessions that are not already present in its parent; it also opens the
   262   session \<^verbatim>\<open>ROOT\<close> entry in the editor to facilitate editing of the main
   263   session. The \<^verbatim>\<open>-S\<close> option is like \<^verbatim>\<open>-R\<close>, with a focus on the selected
   264   session and its descendants: the namespace of accessible theories is
   265   restricted accordingly. This reduces startup time for big projects, notably
   266   the ``Archive of Formal Proofs''. The \<^verbatim>\<open>-A\<close> option specifies and alternative
   267   ancestor session for options \<^verbatim>\<open>-R\<close> and \<^verbatim>\<open>-S\<close>: this allows to restructure the
   268   hierarchy of session images on the spot.
   269 
   270   The \<^verbatim>\<open>-i\<close> option includes additional sessions into the name-space of
   271   theories: multiple occurrences are possible.
   272 
   273   The \<^verbatim>\<open>-m\<close> option specifies additional print modes for the prover process.
   274   Note that the system option @{system_option_ref jedit_print_mode} allows to
   275   do the same persistently (e.g.\ via the \<^emph>\<open>Plugin Options\<close> dialog of
   276   Isabelle/jEdit), without requiring command-line invocation.
   277 
   278   The \<^verbatim>\<open>-J\<close> and \<^verbatim>\<open>-j\<close> options pass additional low-level options to the JVM or
   279   jEdit, respectively. The defaults are provided by the Isabelle settings
   280   environment @{cite "isabelle-system"}, but note that these only work for the
   281   command-line tool described here, and not the regular application.
   282 
   283   The \<^verbatim>\<open>-D\<close> option allows to define JVM system properties; this is passed
   284   directly to the underlying \<^verbatim>\<open>java\<close> process.
   285 
   286   The \<^verbatim>\<open>-b\<close> and \<^verbatim>\<open>-f\<close> options control the self-build mechanism of
   287   Isabelle/jEdit. This is only relevant for building from sources, which also
   288   requires an auxiliary \<^verbatim>\<open>jedit_build\<close> component from
   289   \<^url>\<open>https://isabelle.in.tum.de/components\<close>. The official Isabelle release
   290   already includes a pre-built version of Isabelle/jEdit.
   291 
   292   \<^bigskip>
   293   It is also possible to connect to an already running Isabelle/jEdit process
   294   via @{tool_def jedit_client}:
   295   @{verbatim [display]
   296 \<open>Usage: isabelle jedit_client [OPTIONS] [FILES ...]
   297 
   298   Options are:
   299     -c           only check presence of server
   300     -n           only report server name
   301     -s NAME      server name (default Isabelle)
   302 
   303   Connect to already running Isabelle/jEdit instance and open FILES\<close>}
   304 
   305   The \<^verbatim>\<open>-c\<close> option merely checks the presence of the server, producing a
   306   process return code accordingly.
   307 
   308   The \<^verbatim>\<open>-n\<close> option reports the server name, and the \<^verbatim>\<open>-s\<close> option provides a
   309   different server name. The default server name is the official distribution
   310   name (e.g.\ \<^verbatim>\<open>Isabelle2018\<close>). Thus @{tool jedit_client} can connect to the
   311   Isabelle desktop application without further options.
   312 
   313   The \<^verbatim>\<open>-p\<close> option allows to override the implicit default of the system
   314   option @{system_option_ref ML_process_policy} for ML processes started by
   315   the Prover IDE, e.g. to control CPU affinity on multiprocessor systems.
   316 
   317   The JVM system property \<^verbatim>\<open>isabelle.jedit_server\<close> provides a different server
   318   name, e.g.\ use \<^verbatim>\<open>isabelle jedit -Disabelle.jedit_server=\<close>\<open>name\<close> and
   319   \<^verbatim>\<open>isabelle jedit_client -s\<close>~\<open>name\<close> to connect later on.
   320 \<close>
   321 
   322 
   323 section \<open>GUI rendering\<close>
   324 
   325 subsection \<open>Look-and-feel \label{sec:look-and-feel}\<close>
   326 
   327 text \<open>
   328   jEdit is a Java/AWT/Swing application with the ambition to support
   329   ``native'' look-and-feel on all platforms, within the limits of what Oracle
   330   as Java provider and major operating system distributors allow (see also
   331   \secref{sec:problems}).
   332 
   333   Isabelle/jEdit enables platform-specific look-and-feel by default as
   334   follows.
   335 
   336     \<^descr>[Linux:] The platform-independent \<^emph>\<open>Metal\<close> is used by default.
   337 
   338     The Linux-specific \<^emph>\<open>GTK+\<close> often works as well, but the overall GTK theme
   339     and options need to be selected to suite Java/AWT/Swing. Note that Java
   340     Virtual Machine has no direct influence of GTK rendering.
   341 
   342     \<^descr>[Windows:] Regular \<^emph>\<open>Windows\<close> is used by default.
   343 
   344     \<^descr>[Mac OS X:] Regular \<^emph>\<open>Mac OS X\<close> is used by default.
   345 
   346     The bundled \<^emph>\<open>MacOSX\<close> plugin provides various functions that are expected
   347     from applications on that particular platform: quit from menu or dock,
   348     preferences menu, drag-and-drop of text files on the application,
   349     full-screen mode for main editor windows. It is advisable to have the
   350     \<^emph>\<open>MacOSX\<close> plugin enabled all the time on that platform.
   351 
   352   Users may experiment with different Swing look-and-feels, but need to keep
   353   in mind that this extra variance of GUI functionality often causes problems.
   354   The platform-independent \<^emph>\<open>Metal\<close> and \<^emph>\<open>Nimbus\<close> should always work on all
   355   platforms, although they are technically and stylistically outdated. The
   356   historic \<^emph>\<open>CDE/Motif\<close> should be ignored.
   357 
   358   Changing the look-and-feel in \<^emph>\<open>Global Options~/ Appearance\<close> may update the
   359   GUI only partially: proper restart of Isabelle/jEdit is usually required.
   360 \<close>
   361 
   362 
   363 subsection \<open>Displays with very high resolution \label{sec:hdpi}\<close>
   364 
   365 text \<open>
   366   In distant past, displays with $1024 \times 768$ or $1280 \times 1024$
   367   pixels were considered ``high resolution'' and bitmap fonts with 12 or 14
   368   pixels as adequate for text rendering. After 2016, we have routinely seen
   369   much higher resolutions, e.g. ``Full HD'' at $1920 \times 1080$ pixels or
   370   ``Ultra HD'' / ``4K'' at $3840 \times 2160$.
   371 
   372   GUI frameworks are usually lagging behind, with hard-wired icon sizes and
   373   tiny fonts. Java and jEdit do provide reasonable support for very high
   374   resolution, but this requires manual adjustments as described below.
   375 
   376   \<^medskip>
   377   The \<^bold>\<open>operating-system\<close> usually provides some configuration for global
   378   scaling of text fonts, e.g.\ $120\%$--$250\%$ on Windows. This impacts
   379   regular GUI elements, when used with native look-and-feel: Linux \<^emph>\<open>GTK+\<close>,
   380   \<^emph>\<open>Windows\<close>, \<^emph>\<open>Mac OS X\<close>, respectively. Alternatively, it is possible to use
   381   the platform-independent \<^emph>\<open>Metal\<close> look-and-feel and readjust its main font
   382   sizes via jEdit options explained below. The Isabelle/jEdit \<^bold>\<open>application\<close>
   383   provides further options to adjust font sizes in particular GUI elements.
   384   Here is a summary of all relevant font properties:
   385 
   386     \<^item> \<^emph>\<open>Global Options / Text Area / Text font\<close>: the main text area font,
   387     which is also used as reference point for various derived font sizes,
   388     e.g.\ the \<^emph>\<open>Output\<close> (\secref{sec:output}) and \<^emph>\<open>State\<close>
   389     (\secref{sec:state-output}) panels.
   390 
   391     \<^item> \<^emph>\<open>Global Options / Gutter / Gutter font\<close>: the font for the gutter area
   392     left of the main text area, e.g.\ relevant for display of line numbers
   393     (disabled by default).
   394 
   395     \<^item> \<^emph>\<open>Global Options / Appearance / Button, menu and label font\<close> as well as
   396     \<^emph>\<open>List and text field font\<close>: this specifies the primary and secondary font
   397     for the \<^emph>\<open>Metal\<close> look-and-feel (\secref{sec:look-and-feel}).
   398 
   399     \<^item> \<^emph>\<open>Plugin Options / Isabelle / General / Reset Font Size\<close>: the main text
   400     area font size for action @{action_ref "isabelle.reset-font-size"}, e.g.\
   401     relevant for quick scaling like in common web browsers.
   402 
   403     \<^item> \<^emph>\<open>Plugin Options / Console / General / Font\<close>: the console window font,
   404     e.g.\ relevant for Isabelle/Scala command-line.
   405 
   406   In \figref{fig:isabelle-jedit-hdpi} the \<^emph>\<open>Metal\<close> look-and-feel is configured
   407   with custom fonts at 30 pixels, and the main text area and console at 36
   408   pixels. This leads to decent rendering quality, despite the old-fashioned
   409   appearance of \<^emph>\<open>Metal\<close>.
   410 
   411   \begin{figure}[!htb]
   412   \begin{center}
   413   \includegraphics[width=\textwidth]{isabelle-jedit-hdpi}
   414   \end{center}
   415   \caption{Metal look-and-feel with custom fonts for very high resolution}
   416   \label{fig:isabelle-jedit-hdpi}
   417   \end{figure}
   418 \<close>
   419 
   420 
   421 chapter \<open>Augmented jEdit functionality\<close>
   422 
   423 section \<open>Dockable windows \label{sec:dockables}\<close>
   424 
   425 text \<open>
   426   In jEdit terminology, a \<^emph>\<open>view\<close> is an editor window with one or more \<^emph>\<open>text
   427   areas\<close> that show the content of one or more \<^emph>\<open>buffers\<close>. A regular view may
   428   be surrounded by \<^emph>\<open>dockable windows\<close> that show additional information in
   429   arbitrary format, not just text; a \<^emph>\<open>plain view\<close> does not allow dockables.
   430   The \<^emph>\<open>dockable window manager\<close> of jEdit organizes these dockable windows,
   431   either as \<^emph>\<open>floating\<close> windows, or \<^emph>\<open>docked\<close> panels within one of the four
   432   margins of the view. There may be any number of floating instances of some
   433   dockable window, but at most one docked instance; jEdit actions that address
   434   \<^emph>\<open>the\<close> dockable window of a particular kind refer to the unique docked
   435   instance.
   436 
   437   Dockables are used routinely in jEdit for important functionality like
   438   \<^emph>\<open>HyperSearch Results\<close> or the \<^emph>\<open>File System Browser\<close>. Plugins often provide
   439   a central dockable to access their main functionality, which may be opened
   440   by the user on demand. The Isabelle/jEdit plugin takes this approach to the
   441   extreme: its plugin menu provides the entry-points to many panels that are
   442   managed as dockable windows. Some important panels are docked by default,
   443   e.g.\ \<^emph>\<open>Documentation\<close>, \<^emph>\<open>State\<close>, \<^emph>\<open>Theories\<close> \<^emph>\<open>Output\<close>, \<^emph>\<open>Query\<close>. The user
   444   can change this arrangement easily and persistently.
   445 
   446   Compared to plain jEdit, dockable window management in Isabelle/jEdit is
   447   slightly augmented according to the the following principles:
   448 
   449   \<^item> Floating windows are dependent on the main window as \<^emph>\<open>dialog\<close> in
   450   the sense of Java/AWT/Swing. Dialog windows always stay on top of the view,
   451   which is particularly important in full-screen mode. The desktop environment
   452   of the underlying platform may impose further policies on such dependent
   453   dialogs, in contrast to fully independent windows, e.g.\ some window
   454   management functions may be missing.
   455 
   456   \<^item> Keyboard focus of the main view vs.\ a dockable window is carefully
   457   managed according to the intended semantics, as a panel mainly for output or
   458   input. For example, activating the \<^emph>\<open>Output\<close> (\secref{sec:output}) or State
   459   (\secref{sec:state-output}) panel via the dockable window manager returns
   460   keyboard focus to the main text area, but for \<^emph>\<open>Query\<close> (\secref{sec:query})
   461   or \<^emph>\<open>Sledgehammer\<close> \secref{sec:sledgehammer} the focus is given to the main
   462   input field of that panel.
   463 
   464   \<^item> Panels that provide their own text area for output have an additional
   465   dockable menu item \<^emph>\<open>Detach\<close>. This produces an independent copy of the
   466   current output as a floating \<^emph>\<open>Info\<close> window, which displays that content
   467   independently of ongoing changes of the PIDE document-model. Note that
   468   Isabelle/jEdit popup windows (\secref{sec:tooltips-hyperlinks}) provide a
   469   similar \<^emph>\<open>Detach\<close> operation as an icon.
   470 \<close>
   471 
   472 
   473 section \<open>Isabelle symbols \label{sec:symbols}\<close>
   474 
   475 text \<open>
   476   Isabelle sources consist of \<^emph>\<open>symbols\<close> that extend plain ASCII to allow
   477   infinitely many mathematical symbols within the formal sources. This works
   478   without depending on particular encodings and varying Unicode
   479   standards.\<^footnote>\<open>Raw Unicode characters within formal sources would compromise
   480   portability and reliability in the face of changing interpretation of
   481   special features of Unicode, such as Combining Characters or Bi-directional
   482   Text.\<close> See @{cite "Wenzel:2011:CICM"}.
   483 
   484   For the prover back-end, formal text consists of ASCII characters that are
   485   grouped according to some simple rules, e.g.\ as plain ``\<^verbatim>\<open>a\<close>'' or symbolic
   486   ``\<^verbatim>\<open>\<alpha>\<close>''. For the editor front-end, a certain subset of symbols is rendered
   487   physically via Unicode glyphs, in order to show ``\<^verbatim>\<open>\<alpha>\<close>'' as ``\<open>\<alpha>\<close>'', for
   488   example. This symbol interpretation is specified by the Isabelle system
   489   distribution in \<^file>\<open>$ISABELLE_HOME/etc/symbols\<close> and may be augmented by the
   490   user in @{path "$ISABELLE_HOME_USER/etc/symbols"}.
   491 
   492   The appendix of @{cite "isabelle-isar-ref"} gives an overview of the
   493   standard interpretation of finitely many symbols from the infinite
   494   collection. Uninterpreted symbols are displayed literally, e.g.\
   495   ``\<^verbatim>\<open>\<foobar>\<close>''. Overlap of Unicode characters used in symbol
   496   interpretation with informal ones (which might appear e.g.\ in comments)
   497   needs to be avoided. Raw Unicode characters within prover source files
   498   should be restricted to informal parts, e.g.\ to write text in non-latin
   499   alphabets in comments.
   500 \<close>
   501 
   502 paragraph \<open>Encoding.\<close>
   503 
   504 text \<open>Technically, the Unicode interpretation of Isabelle symbols is an
   505   \<^emph>\<open>encoding\<close> called \<^verbatim>\<open>UTF-8-Isabelle\<close> in jEdit (\<^emph>\<open>not\<close> in the underlying
   506   JVM). It is provided by the Isabelle Base plugin and enabled by default for
   507   all source files in Isabelle/jEdit.
   508 
   509   Sometimes such defaults are reset accidentally, or malformed UTF-8 sequences
   510   in the text force jEdit to fall back on a different encoding like
   511   \<^verbatim>\<open>ISO-8859-15\<close>. In that case, verbatim ``\<^verbatim>\<open>\<alpha>\<close>'' will be shown in the text
   512   buffer instead of its Unicode rendering ``\<open>\<alpha>\<close>''. The jEdit menu operation
   513   \<^emph>\<open>File~/ Reload with Encoding~/ UTF-8-Isabelle\<close> helps to resolve such
   514   problems (after repairing malformed parts of the text).
   515 
   516   If the loaded text already contains Unicode sequences that are in conflict
   517   with the Isabelle symbol encoding, the fallback-encoding UTF-8 is used and
   518   Isabelle symbols remain in literal \<^verbatim>\<open>\<symbol>\<close> form. The jEdit menu
   519   operation \<^emph>\<open>Utilities~/ Buffer Options~/ Character encoding\<close> allows to
   520   enforce the UTF-8-Isabelle, but this will also change original Unicode
   521   text into Isabelle symbols when saving the file!
   522 \<close>
   523 
   524 paragraph \<open>Font.\<close>
   525 text \<open>Correct rendering via Unicode requires a font that contains glyphs for
   526   the corresponding codepoints. There are also various unusual symbols with
   527   particular purpose in Isabelle, e.g.\ control symbols and very long arrows.
   528   Isabelle/jEdit prefers its own font collection \<^verbatim>\<open>Isabelle DejaVu\<close>, which
   529   ensures that all standard Isabelle symbols are shown on the screen (or
   530   printer) as expected.
   531 
   532   Note that a Java/AWT/Swing application can load additional fonts only if
   533   they are not installed on the operating system already! Outdated versions of
   534   Isabelle fonts that happen to be provided by the operating system prevent
   535   Isabelle/jEdit to use its bundled version. This could lead to missing glyphs
   536   (black rectangles), when the system version of a font is older than the
   537   application version. This problem can be avoided by refraining to
   538   ``install'' any version of \<^verbatim>\<open>IsabelleText\<close> in the first place, although it
   539   might be tempting to use the same font in other applications.
   540 
   541   HTML pages generated by Isabelle refer to the same Isabelle fonts as a
   542   server-side resource. Thus a web-browser can use that without requiring a
   543   locally installed copy.
   544 \<close>
   545 
   546 paragraph \<open>Input methods.\<close>
   547 text \<open>In principle, Isabelle/jEdit could delegate the problem to produce
   548   Isabelle symbols in their Unicode rendering to the underlying operating
   549   system and its \<^emph>\<open>input methods\<close>. Regular jEdit also provides various ways to
   550   work with \<^emph>\<open>abbreviations\<close> to produce certain non-ASCII characters. Since
   551   none of these standard input methods work satisfactorily for the
   552   mathematical characters required for Isabelle, various specific
   553   Isabelle/jEdit mechanisms are provided.
   554 
   555   This is a summary for practically relevant input methods for Isabelle
   556   symbols.
   557 
   558   \<^enum> The \<^emph>\<open>Symbols\<close> panel: some GUI buttons allow to insert certain symbols in
   559   the text buffer. There are also tooltips to reveal the official Isabelle
   560   representation with some additional information about \<^emph>\<open>symbol
   561   abbreviations\<close> (see below).
   562 
   563   \<^enum> Copy/paste from decoded source files: text that is rendered as Unicode
   564   already can be re-used to produce further text. This also works between
   565   different applications, e.g.\ Isabelle/jEdit and some web browser or mail
   566   client, as long as the same Unicode interpretation of Isabelle symbols is
   567   used.
   568 
   569   \<^enum> Copy/paste from prover output within Isabelle/jEdit. The same principles
   570   as for text buffers apply, but note that \<^emph>\<open>copy\<close> in secondary Isabelle/jEdit
   571   windows works via the keyboard shortcuts \<^verbatim>\<open>C+c\<close> or \<^verbatim>\<open>C+INSERT\<close>, while jEdit
   572   menu actions always refer to the primary text area!
   573 
   574   \<^enum> Completion provided by the Isabelle plugin (see \secref{sec:completion}).
   575   Isabelle symbols have a canonical name and optional abbreviations. This can
   576   be used with the text completion mechanism of Isabelle/jEdit, to replace a
   577   prefix of the actual symbol like \<^verbatim>\<open>\<lambda>\<close>, or its name preceded by backslash
   578   \<^verbatim>\<open>\lambda\<close>, or its ASCII abbreviation \<^verbatim>\<open>%\<close> by the Unicode rendering.
   579 
   580   The following table is an extract of the information provided by the
   581   standard \<^file>\<open>$ISABELLE_HOME/etc/symbols\<close> file:
   582 
   583   \<^medskip>
   584   \begin{tabular}{lll}
   585     \<^bold>\<open>symbol\<close> & \<^bold>\<open>name with backslash\<close> & \<^bold>\<open>abbreviation\<close> \\\hline
   586     \<open>\<lambda>\<close> & \<^verbatim>\<open>\lambda\<close> & \<^verbatim>\<open>%\<close> \\
   587     \<open>\<Rightarrow>\<close> & \<^verbatim>\<open>\Rightarrow\<close> & \<^verbatim>\<open>=>\<close> \\
   588     \<open>\<Longrightarrow>\<close> & \<^verbatim>\<open>\Longrightarrow\<close> & \<^verbatim>\<open>==>\<close> \\[0.5ex]
   589     \<open>\<And>\<close> & \<^verbatim>\<open>\And\<close> & \<^verbatim>\<open>!!\<close> \\
   590     \<open>\<equiv>\<close> & \<^verbatim>\<open>\equiv\<close> & \<^verbatim>\<open>==\<close> \\[0.5ex]
   591     \<open>\<forall>\<close> & \<^verbatim>\<open>\forall\<close> & \<^verbatim>\<open>!\<close> \\
   592     \<open>\<exists>\<close> & \<^verbatim>\<open>\exists\<close> & \<^verbatim>\<open>?\<close> \\
   593     \<open>\<longrightarrow>\<close> & \<^verbatim>\<open>\longrightarrow\<close> & \<^verbatim>\<open>-->\<close> \\
   594     \<open>\<and>\<close> & \<^verbatim>\<open>\and\<close> & \<^verbatim>\<open>&\<close> \\
   595     \<open>\<or>\<close> & \<^verbatim>\<open>\or\<close> & \<^verbatim>\<open>|\<close> \\
   596     \<open>\<not>\<close> & \<^verbatim>\<open>\not\<close> & \<^verbatim>\<open>~\<close> \\
   597     \<open>\<noteq>\<close> & \<^verbatim>\<open>\noteq\<close> & \<^verbatim>\<open>~=\<close> \\
   598     \<open>\<in>\<close> & \<^verbatim>\<open>\in\<close> & \<^verbatim>\<open>:\<close> \\
   599     \<open>\<notin>\<close> & \<^verbatim>\<open>\notin\<close> & \<^verbatim>\<open>~:\<close> \\
   600   \end{tabular}
   601   \<^medskip>
   602 
   603   Note that the above abbreviations refer to the input method. The logical
   604   notation provides ASCII alternatives that often coincide, but sometimes
   605   deviate. This occasionally causes user confusion with old-fashioned Isabelle
   606   source that use ASCII replacement notation like \<^verbatim>\<open>!\<close> or \<^verbatim>\<open>ALL\<close> directly in
   607   the text.
   608 
   609   On the other hand, coincidence of symbol abbreviations with ASCII
   610   replacement syntax syntax helps to update old theory sources via explicit
   611   completion (see also \<^verbatim>\<open>C+b\<close> explained in \secref{sec:completion}).
   612 \<close>
   613 
   614 paragraph \<open>Control symbols.\<close>
   615 text \<open>There are some special control symbols to modify the display style of a
   616   single symbol (without nesting). Control symbols may be applied to a region
   617   of selected text, either using the \<^emph>\<open>Symbols\<close> panel or keyboard shortcuts or
   618   jEdit actions. These editor operations produce a separate control symbol for
   619   each symbol in the text, in order to make the whole text appear in a certain
   620   style.
   621 
   622   \<^medskip>
   623   \begin{tabular}{llll}
   624     \<^bold>\<open>style\<close> & \<^bold>\<open>symbol\<close> & \<^bold>\<open>shortcut\<close> & \<^bold>\<open>action\<close> \\\hline
   625     superscript & \<^verbatim>\<open>\<^sup>\<close> & \<^verbatim>\<open>C+e UP\<close> & @{action_ref "isabelle.control-sup"} \\
   626     subscript & \<^verbatim>\<open>\<^sub>\<close> & \<^verbatim>\<open>C+e DOWN\<close> & @{action_ref "isabelle.control-sub"} \\
   627     bold face & \<^verbatim>\<open>\<^bold>\<close> & \<^verbatim>\<open>C+e RIGHT\<close> & @{action_ref "isabelle.control-bold"} \\
   628     emphasized & \<^verbatim>\<open>\<^emph>\<close> & \<^verbatim>\<open>C+e LEFT\<close> & @{action_ref "isabelle.control-emph"} \\
   629     reset & & \<^verbatim>\<open>C+e BACK_SPACE\<close> & @{action_ref "isabelle.control-reset"} \\
   630   \end{tabular}
   631   \<^medskip>
   632 
   633   To produce a single control symbol, it is also possible to complete on
   634   \<^verbatim>\<open>\sup\<close>, \<^verbatim>\<open>\sub\<close>, \<^verbatim>\<open>\bold\<close>, \<^verbatim>\<open>\emph\<close> as for regular symbols.
   635 
   636   The emphasized style only takes effect in document output (when used with a
   637   cartouche), but not in the editor.
   638 \<close>
   639 
   640 
   641 section \<open>Scala console \label{sec:scala-console}\<close>
   642 
   643 text \<open>
   644   The \<^emph>\<open>Console\<close> plugin manages various shells (command interpreters), e.g.\
   645   \<^emph>\<open>BeanShell\<close>, which is the official jEdit scripting language, and the
   646   cross-platform \<^emph>\<open>System\<close> shell. Thus the console provides similar
   647   functionality than the Emacs buffers \<^verbatim>\<open>*scratch*\<close> and \<^verbatim>\<open>*shell*\<close>.
   648 
   649   Isabelle/jEdit extends the repertoire of the console by \<^emph>\<open>Scala\<close>, which is
   650   the regular Scala toplevel loop running inside the same JVM process as
   651   Isabelle/jEdit itself. This means the Scala command interpreter has access
   652   to the JVM name space and state of the running Prover IDE application. The
   653   default environment imports the full content of packages \<^verbatim>\<open>isabelle\<close> and
   654   \<^verbatim>\<open>isabelle.jedit\<close>.
   655 
   656   For example, \<^verbatim>\<open>PIDE\<close> refers to the Isabelle/jEdit plugin object, and \<^verbatim>\<open>view\<close>
   657   to the current editor view of jEdit. The Scala expression
   658   \<^verbatim>\<open>PIDE.snapshot(view)\<close> makes a PIDE document snapshot of the current buffer
   659   within the current editor view.
   660 
   661   This helps to explore Isabelle/Scala functionality interactively. Some care
   662   is required to avoid interference with the internals of the running
   663   application.
   664 \<close>
   665 
   666 
   667 section \<open>File-system access\<close>
   668 
   669 text \<open>
   670   File specifications in jEdit follow various formats and conventions
   671   according to \<^emph>\<open>Virtual File Systems\<close>, which may be also provided by
   672   additional plugins. This allows to access remote files via the \<^verbatim>\<open>http:\<close>
   673   protocol prefix, for example. Isabelle/jEdit attempts to work with the
   674   file-system model of jEdit as far as possible. In particular, theory sources
   675   are passed directly from the editor to the prover, without indirection via
   676   physical files.
   677 
   678   Despite the flexibility of URLs in jEdit, local files are particularly
   679   important and are accessible without protocol prefix. The file path notation
   680   is that of the Java Virtual Machine on the underlying platform. On Windows
   681   the preferred form uses backslashes, but happens to accept forward slashes
   682   like Unix/POSIX as well. Further differences arise due to Windows drive
   683   letters and network shares.
   684 
   685   The Java notation for files needs to be distinguished from the one of
   686   Isabelle, which uses POSIX notation with forward slashes on \<^emph>\<open>all\<close>
   687   platforms. Isabelle/ML on Windows uses Unix-style path notation, too, and
   688   driver letter representation as in Cygwin (e.g.\ \<^verbatim>\<open>/cygdrive/c\<close>). Moreover,
   689   environment variables from the Isabelle process may be used freely, e.g.\
   690   \<^file>\<open>$ISABELLE_HOME/etc/symbols\<close> or \<^file>\<open>$POLYML_HOME/README\<close>. There are special
   691   shortcuts: \<^dir>\<open>~\<close> for \<^dir>\<open>$USER_HOME\<close> and \<^dir>\<open>~~\<close> for \<^dir>\<open>$ISABELLE_HOME\<close>.
   692 
   693   \<^medskip>
   694   Since jEdit happens to support environment variables within file
   695   specifications as well, it is natural to use similar notation within the
   696   editor, e.g.\ in the file-browser. This does not work in full generality,
   697   though, due to the bias of jEdit towards platform-specific notation and of
   698   Isabelle towards POSIX. Moreover, the Isabelle settings environment is not
   699   yet active when starting Isabelle/jEdit via its standard application
   700   wrapper, in contrast to @{tool jedit} run from the command line
   701   (\secref{sec:command-line}).
   702 
   703   Isabelle/jEdit imitates important system settings within the Java process
   704   environment, in order to allow easy access to these important places from
   705   the editor: \<^verbatim>\<open>$ISABELLE_HOME\<close>, \<^verbatim>\<open>$ISABELLE_HOME_USER\<close>, \<^verbatim>\<open>$JEDIT_HOME\<close>,
   706   \<^verbatim>\<open>$JEDIT_SETTINGS\<close>. The file browser of jEdit also includes \<^emph>\<open>Favorites\<close> for
   707   these two important locations.
   708 
   709   \<^medskip>
   710   Path specifications in prover input or output usually include formal markup
   711   that turns it into a hyperlink (see also \secref{sec:tooltips-hyperlinks}).
   712   This allows to open the corresponding file in the text editor, independently
   713   of the path notation. If the path refers to a directory, the jEdit file
   714   browser is opened on it.
   715 
   716   Formally checked paths in prover input are subject to completion
   717   (\secref{sec:completion}): partial specifications are resolved via directory
   718   content and possible completions are offered in a popup.
   719 \<close>
   720 
   721 
   722 section \<open>Indentation\<close>
   723 
   724 text \<open>
   725   Isabelle/jEdit augments the existing indentation facilities of jEdit to take
   726   the structure of theory and proof texts into account. There is also special
   727   support for unstructured proof scripts.
   728 
   729     \<^descr>[Syntactic indentation] follows the outer syntax of Isabelle/Isar.
   730 
   731     Action @{action "indent-lines"} (shortcut \<^verbatim>\<open>C+i\<close>) indents the current line
   732     according to command keywords and some command substructure: this
   733     approximation may need further manual tuning.
   734 
   735     Action @{action "isabelle.newline"} (shortcut \<^verbatim>\<open>ENTER\<close>) indents the old
   736     and the new line according to command keywords only: this leads to precise
   737     alignment of the main Isar language elements. This depends on option
   738     @{system_option_def "jedit_indent_newline"} (enabled by default).
   739 
   740     Regular input (via keyboard or completion) indents the current line
   741     whenever an new keyword is emerging at the start of the line. This depends
   742     on option @{system_option_def "jedit_indent_input"} (enabled by default).
   743 
   744     \<^descr>[Semantic indentation] adds additional white space to unstructured proof
   745     scripts (\<^theory_text>\<open>apply\<close> etc.) via number of subgoals. This requires information
   746     of ongoing document processing and may thus lag behind, when the user is
   747     editing too quickly; see also option @{system_option_def
   748     "jedit_script_indent"} and @{system_option_def
   749     "jedit_script_indent_limit"}.
   750 
   751   The above options are accessible in the menu \<^emph>\<open>Plugins / Plugin Options /
   752   Isabelle / General\<close>. A prerequisite for advanced indentation is \<^emph>\<open>Utilities
   753   / Buffer Options / Automatic indentation\<close>: it needs to be set to \<^verbatim>\<open>full\<close>
   754   (default).
   755 \<close>
   756 
   757 
   758 section \<open>SideKick parsers \label{sec:sidekick}\<close>
   759 
   760 text \<open>
   761   The \<^emph>\<open>SideKick\<close> plugin provides some general services to display buffer
   762   structure in a tree view. Isabelle/jEdit provides SideKick parsers for its
   763   main mode for theory files, ML files, as well as some minor modes for the
   764   \<^verbatim>\<open>NEWS\<close> file (see \figref{fig:sidekick}), session \<^verbatim>\<open>ROOT\<close> files, system
   765   \<^verbatim>\<open>options\<close>, and Bib{\TeX} files (\secref{sec:bibtex}).
   766 
   767   \begin{figure}[!htb]
   768   \begin{center}
   769   \includegraphics[scale=0.333]{sidekick}
   770   \end{center}
   771   \caption{The Isabelle NEWS file with SideKick tree view}
   772   \label{fig:sidekick}
   773   \end{figure}
   774 
   775   The default SideKick parser for theory files is \<^verbatim>\<open>isabelle\<close>: it provides a
   776   tree-view on the formal document structure, with section headings at the top
   777   and formal specification elements at the bottom. The alternative parser
   778   \<^verbatim>\<open>isabelle-context\<close> shows nesting of context blocks according to \<^theory_text>\<open>begin \<dots>
   779   end\<close> structure.
   780 
   781   \<^medskip>
   782   Isabelle/ML files are structured according to semi-formal comments that are
   783   explained in @{cite "isabelle-implementation"}. This outline is turned into
   784   a tree-view by default, by using the \<^verbatim>\<open>isabelle-ml\<close> parser. There is also a
   785   folding mode of the same name, for hierarchic text folds within ML files.
   786 
   787   \<^medskip>
   788   The special SideKick parser \<^verbatim>\<open>isabelle-markup\<close> exposes the uninterpreted
   789   markup tree of the PIDE document model of the current buffer. This is
   790   occasionally useful for informative purposes, but the amount of displayed
   791   information might cause problems for large buffers.
   792 \<close>
   793 
   794 
   795 chapter \<open>Prover IDE functionality \label{sec:document-model}\<close>
   796 
   797 section \<open>Document model \label{sec:document-model}\<close>
   798 
   799 text \<open>
   800   The document model is central to the PIDE architecture: the editor and the
   801   prover have a common notion of structured source text with markup, which is
   802   produced by formal processing. The editor is responsible for edits of
   803   document source, as produced by the user. The prover is responsible for
   804   reports of document markup, as produced by its processing in the background.
   805 
   806   Isabelle/jEdit handles classic editor events of jEdit, in order to connect
   807   the physical world of the GUI (with its singleton state) to the mathematical
   808   world of multiple document versions (with timeless and stateless updates).
   809 \<close>
   810 
   811 
   812 subsection \<open>Editor buffers and document nodes \label{sec:buffer-node}\<close>
   813 
   814 text \<open>
   815   As a regular text editor, jEdit maintains a collection of \<^emph>\<open>buffers\<close> to
   816   store text files; each buffer may be associated with any number of visible
   817   \<^emph>\<open>text areas\<close>. Buffers are subject to an \<^emph>\<open>edit mode\<close> that is determined
   818   from the file name extension. The following modes are treated specifically
   819   in Isabelle/jEdit:
   820 
   821   \<^medskip>
   822   \begin{tabular}{lll}
   823   \<^bold>\<open>mode\<close> & \<^bold>\<open>file name\<close> & \<^bold>\<open>content\<close> \\\hline
   824   \<^verbatim>\<open>isabelle\<close> & \<^verbatim>\<open>*.thy\<close> & theory source \\
   825   \<^verbatim>\<open>isabelle-ml\<close> & \<^verbatim>\<open>*.ML\<close> & Isabelle/ML source \\
   826   \<^verbatim>\<open>sml\<close> & \<^verbatim>\<open>*.sml\<close> or \<^verbatim>\<open>*.sig\<close> & Standard ML source \\
   827   \<^verbatim>\<open>isabelle-root\<close> & \<^verbatim>\<open>ROOT\<close> & session root \\
   828   \<^verbatim>\<open>isabelle-options\<close> & & Isabelle options \\
   829   \<^verbatim>\<open>isabelle-news\<close> & & Isabelle NEWS \\
   830   \end{tabular}
   831   \<^medskip>
   832 
   833   All jEdit buffers are automatically added to the PIDE document-model as
   834   \<^emph>\<open>document nodes\<close>. The overall document structure is defined by the theory
   835   nodes in two dimensions:
   836 
   837     \<^enum> via \<^bold>\<open>theory imports\<close> that are specified in the \<^emph>\<open>theory header\<close> using
   838     concrete syntax of the @{command_ref theory} command @{cite
   839     "isabelle-isar-ref"};
   840 
   841     \<^enum> via \<^bold>\<open>auxiliary files\<close> that are included into a theory by \<^emph>\<open>load
   842     commands\<close>, notably @{command_ref ML_file} and @{command_ref SML_file}
   843     @{cite "isabelle-isar-ref"}.
   844 
   845   In any case, source files are managed by the PIDE infrastructure: the
   846   physical file-system only plays a subordinate role. The relevant version of
   847   source text is passed directly from the editor to the prover, using internal
   848   communication channels.
   849 \<close>
   850 
   851 
   852 subsection \<open>Theories \label{sec:theories}\<close>
   853 
   854 text \<open>
   855   The \<^emph>\<open>Theories\<close> panel (see also \figref{fig:theories}) provides an overview
   856   of the status of continuous checking of theory nodes within the document
   857   model.
   858 
   859   \begin{figure}[!htb]
   860   \begin{center}
   861   \includegraphics[scale=0.333]{theories}
   862   \end{center}
   863   \caption{Theories panel with an overview of the document-model, and jEdit
   864   text areas as editable views on some of the document nodes}
   865   \label{fig:theories}
   866   \end{figure}
   867 
   868   Theory imports are resolved automatically by the PIDE document model: all
   869   required files are loaded and stored internally, without the need to open
   870   corresponding jEdit buffers. Opening or closing editor buffers later on has
   871   no direct impact on the formal document content: it only affects visibility.
   872 
   873   In contrast, auxiliary files (e.g.\ from @{command ML_file} commands) are
   874   \<^emph>\<open>not\<close> resolved within the editor by default, but the prover process takes
   875   care of that. This may be changed by enabling the system option
   876   @{system_option jedit_auto_resolve}: it ensures that all files are uniformly
   877   provided by the editor.
   878 
   879   \<^medskip>
   880   The visible \<^emph>\<open>perspective\<close> of Isabelle/jEdit is defined by the collective
   881   view on theory buffers via open text areas. The perspective is taken as a
   882   hint for document processing: the prover ensures that those parts of a
   883   theory where the user is looking are checked, while other parts that are
   884   presently not required are ignored. The perspective is changed by opening or
   885   closing text area windows, or scrolling within a window.
   886 
   887   The \<^emph>\<open>Theories\<close> panel provides some further options to influence the process
   888   of continuous checking: it may be switched off globally to restrict the
   889   prover to superficial processing of command syntax. It is also possible to
   890   indicate theory nodes as \<^emph>\<open>required\<close> for continuous checking: this means
   891   such nodes and all their imports are always processed independently of the
   892   visibility status (if continuous checking is enabled). Big theory libraries
   893   that are marked as required can have significant impact on performance!
   894 
   895   The \<^emph>\<open>Purge\<close> button restricts the document model to theories that are
   896   required for open editor buffers: inaccessible theories are removed and will
   897   be rechecked when opened or imported later.
   898 
   899   \<^medskip>
   900   Formal markup of checked theory content is turned into GUI rendering, based
   901   on a standard repertoire known from mainstream IDEs for programming
   902   languages: colors, icons, highlighting, squiggly underlines, tooltips,
   903   hyperlinks etc. For outer syntax of Isabelle/Isar there is some traditional
   904   syntax-highlighting via static keywords and tokenization within the editor;
   905   this buffer syntax is determined from theory imports. In contrast, the
   906   painting of inner syntax (term language etc.)\ uses semantic information
   907   that is reported dynamically from the logical context. Thus the prover can
   908   provide additional markup to help the user to understand the meaning of
   909   formal text, and to produce more text with some add-on tools (e.g.\
   910   information messages with \<^emph>\<open>sendback\<close> markup by automated provers or
   911   disprovers in the background). \<close>
   912 
   913 
   914 subsection \<open>Auxiliary files \label{sec:aux-files}\<close>
   915 
   916 text \<open>
   917   Special load commands like @{command_ref ML_file} and @{command_ref
   918   SML_file} @{cite "isabelle-isar-ref"} refer to auxiliary files within some
   919   theory. Conceptually, the file argument of the command extends the theory
   920   source by the content of the file, but its editor buffer may be loaded~/
   921   changed~/ saved separately. The PIDE document model propagates changes of
   922   auxiliary file content to the corresponding load command in the theory, to
   923   update and process it accordingly: changes of auxiliary file content are
   924   treated as changes of the corresponding load command.
   925 
   926   \<^medskip>
   927   As a concession to the massive amount of ML files in Isabelle/HOL itself,
   928   the content of auxiliary files is only added to the PIDE document-model on
   929   demand, the first time when opened explicitly in the editor. There are
   930   further tricks to manage markup of ML files, such that Isabelle/HOL may be
   931   edited conveniently in the Prover IDE on small machines with only 8\,GB of
   932   main memory. Using \<^verbatim>\<open>Pure\<close> as logic session image, the exploration may start
   933   at the top \<^file>\<open>$ISABELLE_HOME/src/HOL/Main.thy\<close> or the bottom
   934   \<^file>\<open>$ISABELLE_HOME/src/HOL/HOL.thy\<close>, for example. It is also possible to
   935   explore the Isabelle/Pure bootstrap process (a virtual copy) by opening
   936   \<^file>\<open>$ISABELLE_HOME/src/Pure/ROOT.ML\<close> like a theory in the Prover IDE.
   937 
   938   Initially, before an auxiliary file is opened in the editor, the prover
   939   reads its content from the physical file-system. After the file is opened
   940   for the first time in the editor, e.g.\ by following the hyperlink
   941   (\secref{sec:tooltips-hyperlinks}) for the argument of its @{command
   942   ML_file} command, the content is taken from the jEdit buffer.
   943 
   944   The change of responsibility from prover to editor counts as an update of
   945   the document content, so subsequent theory sources need to be re-checked.
   946   When the buffer is closed, the responsibility remains to the editor: the
   947   file may be opened again without causing another document update.
   948 
   949   A file that is opened in the editor, but its theory with the load command is
   950   not, is presently inactive in the document model. A file that is loaded via
   951   multiple load commands is associated to an arbitrary one: this situation is
   952   morally unsupported and might lead to confusion.
   953 
   954   \<^medskip>
   955   Output that refers to an auxiliary file is combined with that of the
   956   corresponding load command, and shown whenever the file or the command are
   957   active (see also \secref{sec:output}).
   958 
   959   Warnings, errors, and other useful markup is attached directly to the
   960   positions in the auxiliary file buffer, in the manner of standard IDEs. By
   961   using the load command @{command SML_file} as explained in
   962   \<^file>\<open>$ISABELLE_HOME/src/Tools/SML/Examples.thy\<close>, Isabelle/jEdit may be used as
   963   fully-featured IDE for Standard ML, independently of theory or proof
   964   development: the required theory merely serves as some kind of project file
   965   for a collection of SML source modules.
   966 \<close>
   967 
   968 
   969 section \<open>Output \label{sec:output}\<close>
   970 
   971 text \<open>
   972   Prover output consists of \<^emph>\<open>markup\<close> and \<^emph>\<open>messages\<close>. Both are directly
   973   attached to the corresponding positions in the original source text, and
   974   visualized in the text area, e.g.\ as text colours for free and bound
   975   variables, or as squiggly underlines for warnings, errors etc.\ (see also
   976   \figref{fig:output}). In the latter case, the corresponding messages are
   977   shown by hovering with the mouse over the highlighted text --- although in
   978   many situations the user should already get some clue by looking at the
   979   position of the text highlighting, without seeing the message body itself.
   980 
   981   \begin{figure}[!htb]
   982   \begin{center}
   983   \includegraphics[scale=0.333]{output}
   984   \end{center}
   985   \caption{Multiple views on prover output: gutter with icon, text area with
   986   popup, text overview column, \<^emph>\<open>Theories\<close> panel, \<^emph>\<open>Output\<close> panel}
   987   \label{fig:output}
   988   \end{figure}
   989 
   990   The ``gutter'' on the left-hand-side of the text area uses icons to
   991   provide a summary of the messages within the adjacent text line. Message
   992   priorities are used to prefer errors over warnings, warnings over
   993   information messages; other output is ignored.
   994 
   995   The ``text overview column'' on the right-hand-side of the text area uses
   996   similar information to paint small rectangles for the overall status of the
   997   whole text buffer. The graphics is scaled to fit the logical buffer length
   998   into the given window height. Mouse clicks on the overview area move the
   999   cursor approximately to the corresponding text line in the buffer.
  1000 
  1001   The \<^emph>\<open>Theories\<close> panel provides another course-grained overview, but without
  1002   direct correspondence to text positions. The coloured rectangles represent
  1003   the amount of messages of a certain kind (warnings, errors, etc.) and the
  1004   execution status of commands. The border of each rectangle indicates the
  1005   overall status of processing: a thick border means it is \<^emph>\<open>finished\<close> or
  1006   \<^emph>\<open>failed\<close> (with color for errors). A double-click on one of the theory
  1007   entries with their status overview opens the corresponding text buffer,
  1008   without moving the cursor to a specific point.
  1009 
  1010   \<^medskip>
  1011   The \<^emph>\<open>Output\<close> panel displays prover messages that correspond to a given
  1012   command, within a separate window. The cursor position in the presently
  1013   active text area determines the prover command whose cumulative message
  1014   output is appended and shown in that window (in canonical order according to
  1015   the internal execution of the command). There are also control elements to
  1016   modify the update policy of the output wrt.\ continued editor movements:
  1017   \<^emph>\<open>Auto update\<close> and \<^emph>\<open>Update\<close>. This is particularly useful for multiple
  1018   instances of the \<^emph>\<open>Output\<close> panel to look at different situations.
  1019   Alternatively, the panel can be turned into a passive \<^emph>\<open>Info\<close> window via the
  1020   \<^emph>\<open>Detach\<close> menu item.
  1021 
  1022   Proof state is handled separately (\secref{sec:state-output}), but it is
  1023   also possible to tick the corresponding checkbox to append it to regular
  1024   output (\figref{fig:output-including-state}). This is a globally persistent
  1025   option: it affects all open panels and future editor sessions.
  1026 
  1027   \begin{figure}[!htb]
  1028   \begin{center}
  1029   \includegraphics[scale=0.333]{output-including-state}
  1030   \end{center}
  1031   \caption{Proof state display within the regular output panel}
  1032   \label{fig:output-including-state}
  1033   \end{figure}
  1034 
  1035   \<^medskip>
  1036   Following the IDE principle, regular messages are attached to the original
  1037   source in the proper place and may be inspected on demand via popups. This
  1038   excludes messages that are somehow internal to the machinery of proof
  1039   checking, notably \<^emph>\<open>proof state\<close> and \<^emph>\<open>tracing\<close>.
  1040 
  1041   In any case, the same display technology is used for small popups and big
  1042   output windows. The formal text contains markup that may be explored
  1043   recursively via further popups and hyperlinks (see
  1044   \secref{sec:tooltips-hyperlinks}), or clicked directly to initiate certain
  1045   actions (see \secref{sec:auto-tools} and \secref{sec:sledgehammer}).
  1046 \<close>
  1047 
  1048 
  1049 section \<open>Proof state \label{sec:state-output}\<close>
  1050 
  1051 text \<open>
  1052   The main purpose of the Prover IDE is to help the user editing proof
  1053   documents, with ongoing formal checking by the prover in the background.
  1054   This can be done to some extent in the main text area alone, especially for
  1055   well-structured Isar proofs.
  1056 
  1057   Nonetheless, internal proof state needs to be inspected in many situations
  1058   of exploration and ``debugging''. The \<^emph>\<open>State\<close> panel shows exclusively such
  1059   proof state messages without further distraction, while all other messages
  1060   are displayed in \<^emph>\<open>Output\<close> (\secref{sec:output}).
  1061   \Figref{fig:output-and-state} shows a typical GUI layout where both panels
  1062   are open.
  1063 
  1064   \begin{figure}[!htb]
  1065   \begin{center}
  1066   \includegraphics[scale=0.333]{output-and-state}
  1067   \end{center}
  1068   \caption{Separate proof state display (right) and other output (bottom).}
  1069   \label{fig:output-and-state}
  1070   \end{figure}
  1071 
  1072   Another typical arrangement has more than one \<^emph>\<open>State\<close> panel open (as
  1073   floating windows), with \<^emph>\<open>Auto update\<close> disabled to look at an old situation
  1074   while the proof text in the vicinity is changed. The \<^emph>\<open>Update\<close> button
  1075   triggers an explicit one-shot update; this operation is also available via
  1076   the action @{action "isabelle.update-state"} (keyboard shortcut \<^verbatim>\<open>S+ENTER\<close>).
  1077 
  1078   On small screens, it is occasionally useful to have all messages
  1079   concatenated in the regular \<^emph>\<open>Output\<close> panel, e.g.\ see
  1080   \figref{fig:output-including-state}.
  1081 
  1082   \<^medskip>
  1083   The mechanics of \<^emph>\<open>Output\<close> versus \<^emph>\<open>State\<close> are slightly different:
  1084 
  1085     \<^item> \<^emph>\<open>Output\<close> shows information that is continuously produced and already
  1086     present when the GUI wants to show it. This is implicitly controlled by
  1087     the visible perspective on the text.
  1088 
  1089     \<^item> \<^emph>\<open>State\<close> initiates a real-time query on demand, with a full round trip
  1090     including a fresh print operation on the prover side. This is controlled
  1091     explicitly when the cursor is moved to the next command (\<^emph>\<open>Auto update\<close>)
  1092     or the \<^emph>\<open>Update\<close> operation is triggered.
  1093 
  1094   This can make a difference in GUI responsibility and resource usage within
  1095   the prover process. Applications with very big proof states that are only
  1096   inspected in isolation work better with the \<^emph>\<open>State\<close> panel.
  1097 \<close>
  1098 
  1099 
  1100 section \<open>Query \label{sec:query}\<close>
  1101 
  1102 text \<open>
  1103   The \<^emph>\<open>Query\<close> panel provides various GUI forms to request extra information
  1104   from the prover, as a replacement of old-style diagnostic commands like
  1105   @{command find_theorems}. There are input fields and buttons for a
  1106   particular query command, with output in a dedicated text area.
  1107 
  1108   The main query modes are presented as separate tabs: \<^emph>\<open>Find Theorems\<close>,
  1109   \<^emph>\<open>Find Constants\<close>, \<^emph>\<open>Print Context\<close>, e.g.\ see \figref{fig:query}. As usual
  1110   in jEdit, multiple \<^emph>\<open>Query\<close> windows may be active at the same time: any
  1111   number of floating instances, but at most one docked instance (which is used
  1112   by default).
  1113 
  1114   \begin{figure}[!htb]
  1115   \begin{center}
  1116   \includegraphics[scale=0.333]{query}
  1117   \end{center}
  1118   \caption{An instance of the Query panel: find theorems}
  1119   \label{fig:query}
  1120   \end{figure}
  1121 
  1122   \<^medskip>
  1123   The following GUI elements are common to all query modes:
  1124 
  1125     \<^item> The spinning wheel provides feedback about the status of a pending query
  1126     wrt.\ the evaluation of its context and its own operation.
  1127 
  1128     \<^item> The \<^emph>\<open>Apply\<close> button attaches a fresh query invocation to the current
  1129     context of the command where the cursor is pointing in the text.
  1130 
  1131     \<^item> The \<^emph>\<open>Search\<close> field allows to highlight query output according to some
  1132     regular expression, in the notation that is commonly used on the Java
  1133     platform.\<^footnote>\<open>\<^url>\<open>https://docs.oracle.com/javase/8/docs/api/java/util/regex/Pattern.html\<close>\<close>
  1134     This may serve as an additional visual filter of the result.
  1135 
  1136     \<^item> The \<^emph>\<open>Zoom\<close> box controls the font size of the output area.
  1137 
  1138   All query operations are asynchronous: there is no need to wait for the
  1139   evaluation of the document for the query context, nor for the query
  1140   operation itself. Query output may be detached as independent \<^emph>\<open>Info\<close>
  1141   window, using a menu operation of the dockable window manager. The printed
  1142   result usually provides sufficient clues about the original query, with some
  1143   hyperlink to its context (via markup of its head line).
  1144 \<close>
  1145 
  1146 
  1147 subsection \<open>Find theorems\<close>
  1148 
  1149 text \<open>
  1150   The \<^emph>\<open>Query\<close> panel in \<^emph>\<open>Find Theorems\<close> mode retrieves facts from the theory
  1151   or proof context matching all of given criteria in the \<^emph>\<open>Find\<close> text field. A
  1152   single criterion has the following syntax:
  1153 
  1154   @{rail \<open>
  1155     ('-'?) ('name' ':' @{syntax name} | 'intro' | 'elim' | 'dest' |
  1156       'solves' | 'simp' ':' @{syntax term} | @{syntax term})
  1157   \<close>}
  1158 
  1159   See also the Isar command @{command_ref find_theorems} in @{cite
  1160   "isabelle-isar-ref"}.
  1161 \<close>
  1162 
  1163 
  1164 subsection \<open>Find constants\<close>
  1165 
  1166 text \<open>
  1167   The \<^emph>\<open>Query\<close> panel in \<^emph>\<open>Find Constants\<close> mode prints all constants whose type
  1168   meets all of the given criteria in the \<^emph>\<open>Find\<close> text field. A single
  1169   criterion has the following syntax:
  1170 
  1171   @{rail \<open>
  1172     ('-'?)
  1173       ('name' ':' @{syntax name} | 'strict' ':' @{syntax type} | @{syntax type})
  1174   \<close>}
  1175 
  1176   See also the Isar command @{command_ref find_consts} in @{cite
  1177   "isabelle-isar-ref"}.
  1178 \<close>
  1179 
  1180 
  1181 subsection \<open>Print context\<close>
  1182 
  1183 text \<open>
  1184   The \<^emph>\<open>Query\<close> panel in \<^emph>\<open>Print Context\<close> mode prints information from the
  1185   theory or proof context, or proof state. See also the Isar commands
  1186   @{command_ref print_context}, @{command_ref print_cases}, @{command_ref
  1187   print_term_bindings}, @{command_ref print_theorems}, described in @{cite
  1188   "isabelle-isar-ref"}.
  1189 \<close>
  1190 
  1191 
  1192 section \<open>Tooltips and hyperlinks \label{sec:tooltips-hyperlinks}\<close>
  1193 
  1194 text \<open>
  1195   Formally processed text (prover input or output) contains rich markup that
  1196   can be explored by using the \<^verbatim>\<open>CONTROL\<close> modifier key on Linux and Windows,
  1197   or \<^verbatim>\<open>COMMAND\<close> on Mac OS X. Hovering with the mouse while the modifier is
  1198   pressed reveals a \<^emph>\<open>tooltip\<close> (grey box over the text with a yellow popup)
  1199   and/or a \<^emph>\<open>hyperlink\<close> (black rectangle over the text with change of mouse
  1200   pointer); see also \figref{fig:tooltip}.
  1201 
  1202   \begin{figure}[!htb]
  1203   \begin{center}
  1204   \includegraphics[scale=0.5]{popup1}
  1205   \end{center}
  1206   \caption{Tooltip and hyperlink for some formal entity}
  1207   \label{fig:tooltip}
  1208   \end{figure}
  1209 
  1210   Tooltip popups use the same rendering technology as the main text area, and
  1211   further tooltips and/or hyperlinks may be exposed recursively by the same
  1212   mechanism; see \figref{fig:nested-tooltips}.
  1213 
  1214   \begin{figure}[!htb]
  1215   \begin{center}
  1216   \includegraphics[scale=0.5]{popup2}
  1217   \end{center}
  1218   \caption{Nested tooltips over formal entities}
  1219   \label{fig:nested-tooltips}
  1220   \end{figure}
  1221 
  1222   The tooltip popup window provides some controls to \<^emph>\<open>close\<close> or \<^emph>\<open>detach\<close> the
  1223   window, turning it into a separate \<^emph>\<open>Info\<close> window managed by jEdit. The
  1224   \<^verbatim>\<open>ESCAPE\<close> key closes \<^emph>\<open>all\<close> popups, which is particularly relevant when
  1225   nested tooltips are stacking up.
  1226 
  1227   \<^medskip>
  1228   A black rectangle in the text indicates a hyperlink that may be followed by
  1229   a mouse click (while the \<^verbatim>\<open>CONTROL\<close> or \<^verbatim>\<open>COMMAND\<close> modifier key is still
  1230   pressed). Such jumps to other text locations are recorded by the
  1231   \<^emph>\<open>Navigator\<close> plugin, which is bundled with Isabelle/jEdit and enabled by
  1232   default. There are usually navigation arrows in the main jEdit toolbar.
  1233 
  1234   Note that the link target may be a file that is itself not subject to formal
  1235   document processing of the editor session and thus prevents further
  1236   exploration: the chain of hyperlinks may end in some source file of the
  1237   underlying logic image, or within the ML bootstrap sources of Isabelle/Pure.
  1238 \<close>
  1239 
  1240 
  1241 section \<open>Formal scopes and semantic selection\<close>
  1242 
  1243 text \<open>
  1244   Formal entities are semantically annotated in the source text as explained
  1245   in \secref{sec:tooltips-hyperlinks}. A \<^emph>\<open>formal scope\<close> consists of the
  1246   defining position with all its referencing positions. This correspondence is
  1247   highlighted in the text according to the cursor position, see also
  1248   \figref{fig:scope1}. Here the referencing positions are rendered with an
  1249   additional border, in reminiscence to a hyperlink: clicking there moves the
  1250   cursor to the original defining position.
  1251 
  1252   \begin{figure}[!htb]
  1253   \begin{center}
  1254   \includegraphics[scale=0.5]{scope1}
  1255   \end{center}
  1256   \caption{Scope of formal entity: defining vs.\ referencing positions}
  1257   \label{fig:scope1}
  1258   \end{figure}
  1259 
  1260   The action @{action_def "isabelle.select-entity"} (shortcut \<^verbatim>\<open>CS+ENTER\<close>)
  1261   supports semantic selection of all occurrences of the formal entity at the
  1262   caret position. This facilitates systematic renaming, using regular jEdit
  1263   editing of a multi-selection, see also \figref{fig:scope2}.
  1264 
  1265   \begin{figure}[!htb]
  1266   \begin{center}
  1267   \includegraphics[scale=0.5]{scope2}
  1268   \end{center}
  1269   \caption{The result of semantic selection and systematic renaming}
  1270   \label{fig:scope2}
  1271   \end{figure}
  1272 \<close>
  1273 
  1274 
  1275 section \<open>Completion \label{sec:completion}\<close>
  1276 
  1277 text \<open>
  1278   Smart completion of partial input is the IDE functionality \<^emph>\<open>par
  1279   excellance\<close>. Isabelle/jEdit combines several sources of information to
  1280   achieve that. Despite its complexity, it should be possible to get some idea
  1281   how completion works by experimentation, based on the overview of completion
  1282   varieties in \secref{sec:completion-varieties}. The remaining subsections
  1283   explain concepts around completion more systematically.
  1284 
  1285   \<^medskip>
  1286   \<^emph>\<open>Explicit completion\<close> is triggered by the action @{action_ref
  1287   "isabelle.complete"}, which is bound to the keyboard shortcut \<^verbatim>\<open>C+b\<close>, and
  1288   thus overrides the jEdit default for @{action_ref "complete-word"}.
  1289 
  1290   \<^emph>\<open>Implicit completion\<close> hooks into the regular keyboard input stream of the
  1291   editor, with some event filtering and optional delays.
  1292 
  1293   \<^medskip>
  1294   Completion options may be configured in \<^emph>\<open>Plugin Options~/ Isabelle~/
  1295   General~/ Completion\<close>. These are explained in further detail below, whenever
  1296   relevant. There is also a summary of options in
  1297   \secref{sec:completion-options}.
  1298 
  1299   The asynchronous nature of PIDE interaction means that information from the
  1300   prover is delayed --- at least by a full round-trip of the document update
  1301   protocol. The default options already take this into account, with a
  1302   sufficiently long completion delay to speculate on the availability of all
  1303   relevant information from the editor and the prover, before completing text
  1304   immediately or producing a popup. Although there is an inherent danger of
  1305   non-deterministic behaviour due to such real-time parameters, the general
  1306   completion policy aims at determined results as far as possible.
  1307 \<close>
  1308 
  1309 
  1310 subsection \<open>Varieties of completion \label{sec:completion-varieties}\<close>
  1311 
  1312 subsubsection \<open>Built-in templates\<close>
  1313 
  1314 text \<open>
  1315   Isabelle is ultimately a framework of nested sub-languages of different
  1316   kinds and purposes. The completion mechanism supports this by the following
  1317   built-in templates:
  1318 
  1319     \<^descr> \<^verbatim>\<open>`\<close> (single ASCII back-quote) or \<^verbatim>\<open>"\<close> (double ASCII quote) support
  1320     \<^emph>\<open>quotations\<close> via text cartouches. There are three selections, which are
  1321     always presented in the same order and do not depend on any context
  1322     information. The default choice produces a template ``\<open>\<open>\<box>\<close>\<close>'', where the
  1323     box indicates the cursor position after insertion; the other choices help
  1324     to repair the block structure of unbalanced text cartouches.
  1325 
  1326     \<^descr> \<^verbatim>\<open>@{\<close> is completed to the template ``\<open>@{\<box>}\<close>'', where the box indicates
  1327     the cursor position after insertion. Here it is convenient to use the
  1328     wildcard ``\<^verbatim>\<open>__\<close>'' or a more specific name prefix to let semantic
  1329     completion of name-space entries propose antiquotation names.
  1330 
  1331   With some practice, input of quoted sub-languages and antiquotations of
  1332   embedded languages should work fluently. Note that national keyboard layouts
  1333   might cause problems with back-quote as dead key, but double quote can be
  1334   used instead.
  1335 \<close>
  1336 
  1337 
  1338 subsubsection \<open>Syntax keywords\<close>
  1339 
  1340 text \<open>
  1341   Syntax completion tables are determined statically from the keywords of the
  1342   ``outer syntax'' of the underlying edit mode: for theory files this is the
  1343   syntax of Isar commands according to the cumulative theory imports.
  1344 
  1345   Keywords are usually plain words, which means the completion mechanism only
  1346   inserts them directly into the text for explicit completion
  1347   (\secref{sec:completion-input}), but produces a popup
  1348   (\secref{sec:completion-popup}) otherwise.
  1349 
  1350   At the point where outer syntax keywords are defined, it is possible to
  1351   specify an alternative replacement string to be inserted instead of the
  1352   keyword itself. An empty string means to suppress the keyword altogether,
  1353   which is occasionally useful to avoid confusion, e.g.\ the rare keyword
  1354   @{command simproc_setup} vs.\ the frequent name-space entry \<open>simp\<close>.
  1355 \<close>
  1356 
  1357 
  1358 subsubsection \<open>Isabelle symbols\<close>
  1359 
  1360 text \<open>
  1361   The completion tables for Isabelle symbols (\secref{sec:symbols}) are
  1362   determined statically from \<^file>\<open>$ISABELLE_HOME/etc/symbols\<close> and @{path
  1363   "$ISABELLE_HOME_USER/etc/symbols"} for each symbol specification as follows:
  1364 
  1365   \<^medskip>
  1366   \begin{tabular}{ll}
  1367   \<^bold>\<open>completion entry\<close> & \<^bold>\<open>example\<close> \\\hline
  1368   literal symbol & \<^verbatim>\<open>\<forall>\<close> \\
  1369   symbol name with backslash & \<^verbatim>\<open>\\<close>\<^verbatim>\<open>forall\<close> \\
  1370   symbol abbreviation & \<^verbatim>\<open>ALL\<close> or \<^verbatim>\<open>!\<close> \\
  1371   \end{tabular}
  1372   \<^medskip>
  1373 
  1374   When inserted into the text, the above examples all produce the same Unicode
  1375   rendering \<open>\<forall>\<close> of the underlying symbol \<^verbatim>\<open>\<forall>\<close>.
  1376 
  1377   A symbol abbreviation that is a plain word, like \<^verbatim>\<open>ALL\<close>, is treated like a
  1378   syntax keyword. Non-word abbreviations like \<^verbatim>\<open>-->\<close> are inserted more
  1379   aggressively, except for single-character abbreviations like \<^verbatim>\<open>!\<close> above.
  1380 
  1381   Completion via abbreviations like \<^verbatim>\<open>ALL\<close> or \<^verbatim>\<open>-->\<close> depends on the semantic
  1382   language context (\secref{sec:completion-context}). In contrast, backslash
  1383   sequences like \<^verbatim>\<open>\forall\<close> \<^verbatim>\<open>\<forall>\<close> are always possible, but require additional
  1384   interaction to confirm (via popup). This is important in ambiguous
  1385   situations, e.g.\ for Isabelle document source, which may contain formal
  1386   symbols or informal {\LaTeX} macros. Backslash sequences also help when
  1387   input is broken, and thus escapes its normal semantic context: e.g.\
  1388   antiquotations or string literals in ML, which do not allow arbitrary
  1389   backslash sequences.
  1390 
  1391   Special symbols like \<^verbatim>\<open>\<comment>\<close> or control symbols like \<^verbatim>\<open>\<^cancel>\<close>,
  1392   \<^verbatim>\<open>\<^latex>\<close>, \<^verbatim>\<open>\<^binding>\<close> can have an argument: completing on a name
  1393   prefix offers a template with an empty cartouche. Thus completion of \<^verbatim>\<open>\co\<close>
  1394   or \<^verbatim>\<open>\ca\<close> allows to compose formal document comments quickly.\<^footnote>\<open>It is
  1395   customary to put a space between \<^verbatim>\<open>\<comment>\<close> and its argument, while
  1396   control symbols do \<^emph>\<open>not\<close> allow extra space here.\<close>
  1397 \<close>
  1398 
  1399 
  1400 subsubsection \<open>User-defined abbreviations\<close>
  1401 
  1402 text \<open>
  1403   The theory header syntax supports abbreviations via the \<^theory_text>\<open>abbrevs\<close> keyword
  1404   @{cite "isabelle-isar-ref"}. This is a slight generalization of built-in
  1405   templates and abbreviations for Isabelle symbols, as explained above.
  1406   Examples may be found in the Isabelle sources, by searching for
  1407   ``\<^verbatim>\<open>abbrevs\<close>'' in \<^verbatim>\<open>*.thy\<close> files.
  1408 
  1409   The \<^emph>\<open>Symbols\<close> panel shows the abbreviations that are available in the
  1410   current theory buffer (according to its \<^theory_text>\<open>imports\<close>) in the \<^verbatim>\<open>Abbrevs\<close> tab.
  1411 \<close>
  1412 
  1413 
  1414 subsubsection \<open>Name-space entries\<close>
  1415 
  1416 text \<open>
  1417   This is genuine semantic completion, using information from the prover, so
  1418   it requires some delay. A \<^emph>\<open>failed name-space lookup\<close> produces an error
  1419   message that is annotated with a list of alternative names that are legal.
  1420   The list of results is truncated according to the system option
  1421   @{system_option_ref completion_limit}. The completion mechanism takes this
  1422   into account when collecting information on the prover side.
  1423 
  1424   Already recognized names are \<^emph>\<open>not\<close> completed further, but completion may be
  1425   extended by appending a suffix of underscores. This provokes a failed
  1426   lookup, and another completion attempt while ignoring the underscores. For
  1427   example, in a name space where \<^verbatim>\<open>foo\<close> and \<^verbatim>\<open>foobar\<close> are known, the input
  1428   \<^verbatim>\<open>foo\<close> remains unchanged, but \<^verbatim>\<open>foo_\<close> may be completed to \<^verbatim>\<open>foo\<close> or
  1429   \<^verbatim>\<open>foobar\<close>.
  1430 
  1431   The special identifier ``\<^verbatim>\<open>__\<close>'' serves as a wild-card for arbitrary
  1432   completion: it exposes the name-space content to the completion mechanism
  1433   (truncated according to @{system_option completion_limit}). This is
  1434   occasionally useful to explore an unknown name-space, e.g.\ in some
  1435   template.
  1436 \<close>
  1437 
  1438 
  1439 subsubsection \<open>File-system paths\<close>
  1440 
  1441 text \<open>
  1442   Depending on prover markup about file-system paths in the source text, e.g.\
  1443   for the argument of a load command (\secref{sec:aux-files}), the completion
  1444   mechanism explores the directory content and offers the result as completion
  1445   popup. Relative path specifications are understood wrt.\ the \<^emph>\<open>master
  1446   directory\<close> of the document node (\secref{sec:buffer-node}) of the enclosing
  1447   editor buffer; this requires a proper theory, not an auxiliary file.
  1448 
  1449   A suffix of slashes may be used to continue the exploration of an already
  1450   recognized directory name.
  1451 \<close>
  1452 
  1453 
  1454 subsubsection \<open>Spell-checking\<close>
  1455 
  1456 text \<open>
  1457   The spell-checker combines semantic markup from the prover (regions of plain
  1458   words) with static dictionaries (word lists) that are known to the editor.
  1459 
  1460   Unknown words are underlined in the text, using @{system_option_ref
  1461   spell_checker_color} (blue by default). This is not an error, but a hint to
  1462   the user that some action may be taken. The jEdit context menu provides
  1463   various actions, as far as applicable:
  1464 
  1465   \<^medskip>
  1466   \begin{tabular}{l}
  1467   @{action_ref "isabelle.complete-word"} \\
  1468   @{action_ref "isabelle.exclude-word"} \\
  1469   @{action_ref "isabelle.exclude-word-permanently"} \\
  1470   @{action_ref "isabelle.include-word"} \\
  1471   @{action_ref "isabelle.include-word-permanently"} \\
  1472   \end{tabular}
  1473   \<^medskip>
  1474 
  1475   Instead of the specific @{action_ref "isabelle.complete-word"}, it is also
  1476   possible to use the generic @{action_ref "isabelle.complete"} with its
  1477   default keyboard shortcut \<^verbatim>\<open>C+b\<close>.
  1478 
  1479   \<^medskip>
  1480   Dictionary lookup uses some educated guesses about lower-case, upper-case,
  1481   and capitalized words. This is oriented on common use in English, where this
  1482   aspect is not decisive for proper spelling (in contrast to German, for
  1483   example).
  1484 \<close>
  1485 
  1486 
  1487 subsection \<open>Semantic completion context \label{sec:completion-context}\<close>
  1488 
  1489 text \<open>
  1490   Completion depends on a semantic context that is provided by the prover,
  1491   although with some delay, because at least a full PIDE protocol round-trip
  1492   is required. Until that information becomes available in the PIDE
  1493   document-model, the default context is given by the outer syntax of the
  1494   editor mode (see also \secref{sec:buffer-node}).
  1495 
  1496   The semantic \<^emph>\<open>language context\<close> provides information about nested
  1497   sub-languages of Isabelle: keywords are only completed for outer syntax, and
  1498   antiquotations for languages that support them. Symbol abbreviations only
  1499   work for specific sub-languages: e.g.\ ``\<^verbatim>\<open>=>\<close>'' is \<^emph>\<open>not\<close> completed in
  1500   regular ML source, but is completed within ML strings, comments,
  1501   antiquotations. Backslash representations of symbols like ``\<^verbatim>\<open>\foobar\<close>'' or
  1502   ``\<^verbatim>\<open>\<foobar>\<close>'' work in any context --- after additional confirmation.
  1503 
  1504   The prover may produce \<^emph>\<open>no completion\<close> markup in exceptional situations, to
  1505   tell that some language keywords should be excluded from further completion
  1506   attempts. For example, ``\<^verbatim>\<open>:\<close>'' within accepted Isar syntax looses its
  1507   meaning as abbreviation for symbol ``\<open>\<in>\<close>''.
  1508 \<close>
  1509 
  1510 
  1511 subsection \<open>Input events \label{sec:completion-input}\<close>
  1512 
  1513 text \<open>
  1514   Completion is triggered by certain events produced by the user, with
  1515   optional delay after keyboard input according to @{system_option
  1516   jedit_completion_delay}.
  1517 
  1518   \<^descr>[Explicit completion] works via action @{action_ref "isabelle.complete"}
  1519   with keyboard shortcut \<^verbatim>\<open>C+b\<close>. This overrides the shortcut for @{action_ref
  1520   "complete-word"} in jEdit, but it is possible to restore the original jEdit
  1521   keyboard mapping of @{action "complete-word"} via \<^emph>\<open>Global Options~/
  1522   Shortcuts\<close> and invent a different one for @{action "isabelle.complete"}.
  1523 
  1524   \<^descr>[Explicit spell-checker completion] works via @{action_ref
  1525   "isabelle.complete-word"}, which is exposed in the jEdit context menu, if
  1526   the mouse points to a word that the spell-checker can complete.
  1527 
  1528   \<^descr>[Implicit completion] works via regular keyboard input of the editor. It
  1529   depends on further side-conditions:
  1530 
  1531     \<^enum> The system option @{system_option_ref jedit_completion} needs to be
  1532     enabled (default).
  1533 
  1534     \<^enum> Completion of syntax keywords requires at least 3 relevant characters in
  1535     the text.
  1536 
  1537     \<^enum> The system option @{system_option_ref jedit_completion_delay} determines
  1538     an additional delay (0.5 by default), before opening a completion popup.
  1539     The delay gives the prover a chance to provide semantic completion
  1540     information, notably the context (\secref{sec:completion-context}).
  1541 
  1542     \<^enum> The system option @{system_option_ref jedit_completion_immediate}
  1543     (enabled by default) controls whether replacement text should be inserted
  1544     immediately without popup, regardless of @{system_option
  1545     jedit_completion_delay}. This aggressive mode of completion is restricted
  1546     to symbol abbreviations that are not plain words (\secref{sec:symbols}).
  1547 
  1548     \<^enum> Completion of symbol abbreviations with only one relevant character in
  1549     the text always enforces an explicit popup, regardless of
  1550     @{system_option_ref jedit_completion_immediate}.
  1551 \<close>
  1552 
  1553 
  1554 subsection \<open>Completion popup \label{sec:completion-popup}\<close>
  1555 
  1556 text \<open>
  1557   A \<^emph>\<open>completion popup\<close> is a minimally invasive GUI component over the text
  1558   area that offers a selection of completion items to be inserted into the
  1559   text, e.g.\ by mouse clicks. Items are sorted dynamically, according to the
  1560   frequency of selection, with persistent history. The popup may interpret
  1561   special keys \<^verbatim>\<open>ENTER\<close>, \<^verbatim>\<open>TAB\<close>, \<^verbatim>\<open>ESCAPE\<close>, \<^verbatim>\<open>UP\<close>, \<^verbatim>\<open>DOWN\<close>, \<^verbatim>\<open>PAGE_UP\<close>,
  1562   \<^verbatim>\<open>PAGE_DOWN\<close>, but all other key events are passed to the underlying text
  1563   area. This allows to ignore unwanted completions most of the time and
  1564   continue typing quickly. Thus the popup serves as a mechanism of
  1565   confirmation of proposed items, while the default is to continue without
  1566   completion.
  1567 
  1568   The meaning of special keys is as follows:
  1569 
  1570   \<^medskip>
  1571   \begin{tabular}{ll}
  1572   \<^bold>\<open>key\<close> & \<^bold>\<open>action\<close> \\\hline
  1573   \<^verbatim>\<open>ENTER\<close> & select completion (if @{system_option jedit_completion_select_enter}) \\
  1574   \<^verbatim>\<open>TAB\<close> & select completion (if @{system_option jedit_completion_select_tab}) \\
  1575   \<^verbatim>\<open>ESCAPE\<close> & dismiss popup \\
  1576   \<^verbatim>\<open>UP\<close> & move up one item \\
  1577   \<^verbatim>\<open>DOWN\<close> & move down one item \\
  1578   \<^verbatim>\<open>PAGE_UP\<close> & move up one page of items \\
  1579   \<^verbatim>\<open>PAGE_DOWN\<close> & move down one page of items \\
  1580   \end{tabular}
  1581   \<^medskip>
  1582 
  1583   Movement within the popup is only active for multiple items. Otherwise the
  1584   corresponding key event retains its standard meaning within the underlying
  1585   text area.
  1586 \<close>
  1587 
  1588 
  1589 subsection \<open>Insertion \label{sec:completion-insert}\<close>
  1590 
  1591 text \<open>
  1592   Completion may first propose replacements to be selected (via a popup), or
  1593   replace text immediately in certain situations and depending on certain
  1594   options like @{system_option jedit_completion_immediate}. In any case,
  1595   insertion works uniformly, by imitating normal jEdit text insertion,
  1596   depending on the state of the \<^emph>\<open>text selection\<close>. Isabelle/jEdit tries to
  1597   accommodate the most common forms of advanced selections in jEdit, but not
  1598   all combinations make sense. At least the following important cases are
  1599   well-defined:
  1600 
  1601     \<^descr>[No selection.] The original is removed and the replacement inserted,
  1602     depending on the caret position.
  1603 
  1604     \<^descr>[Rectangular selection of zero width.] This special case is treated by
  1605     jEdit as ``tall caret'' and insertion of completion imitates its normal
  1606     behaviour: separate copies of the replacement are inserted for each line
  1607     of the selection.
  1608 
  1609     \<^descr>[Other rectangular selection or multiple selections.] Here the original
  1610     is removed and the replacement is inserted for each line (or segment) of
  1611     the selection.
  1612 
  1613   Support for multiple selections is particularly useful for \<^emph>\<open>HyperSearch\<close>:
  1614   clicking on one of the items in the \<^emph>\<open>HyperSearch Results\<close> window makes
  1615   jEdit select all its occurrences in the corresponding line of text. Then
  1616   explicit completion can be invoked via \<^verbatim>\<open>C+b\<close>, e.g.\ to replace occurrences
  1617   of \<^verbatim>\<open>-->\<close> by \<open>\<longrightarrow>\<close>.
  1618 
  1619   \<^medskip>
  1620   Insertion works by removing and inserting pieces of text from the buffer.
  1621   This counts as one atomic operation on the jEdit history. Thus unintended
  1622   completions may be reverted by the regular @{action undo} action of jEdit.
  1623   According to normal jEdit policies, the recovered text after @{action undo}
  1624   is selected: \<^verbatim>\<open>ESCAPE\<close> is required to reset the selection and to continue
  1625   typing more text.
  1626 \<close>
  1627 
  1628 
  1629 subsection \<open>Options \label{sec:completion-options}\<close>
  1630 
  1631 text \<open>
  1632   This is a summary of Isabelle/Scala system options that are relevant for
  1633   completion. They may be configured in \<^emph>\<open>Plugin Options~/ Isabelle~/ General\<close>
  1634   as usual.
  1635 
  1636   \<^item> @{system_option_def completion_limit} specifies the maximum number of
  1637   items for various semantic completion operations (name-space entries etc.)
  1638 
  1639   \<^item> @{system_option_def jedit_completion} guards implicit completion via
  1640   regular jEdit key events (\secref{sec:completion-input}): it allows to
  1641   disable implicit completion altogether.
  1642 
  1643   \<^item> @{system_option_def jedit_completion_select_enter} and @{system_option_def
  1644   jedit_completion_select_tab} enable keys to select a completion item from
  1645   the popup (\secref{sec:completion-popup}). Note that a regular mouse click
  1646   on the list of items is always possible.
  1647 
  1648   \<^item> @{system_option_def jedit_completion_context} specifies whether the
  1649   language context provided by the prover should be used at all. Disabling
  1650   that option makes completion less ``semantic''. Note that incomplete or
  1651   severely broken input may cause some disagreement of the prover and the user
  1652   about the intended language context.
  1653 
  1654   \<^item> @{system_option_def jedit_completion_delay} and @{system_option_def
  1655   jedit_completion_immediate} determine the handling of keyboard events for
  1656   implicit completion (\secref{sec:completion-input}).
  1657 
  1658   A @{system_option jedit_completion_delay}~\<^verbatim>\<open>> 0\<close> postpones the processing of
  1659   key events, until after the user has stopped typing for the given time span,
  1660   but @{system_option jedit_completion_immediate}~\<^verbatim>\<open>= true\<close> means that
  1661   abbreviations of Isabelle symbols are handled nonetheless.
  1662 
  1663   \<^item> @{system_option_def completion_path_ignore} specifies ``glob''
  1664   patterns to ignore in file-system path completion (separated by colons),
  1665   e.g.\ backup files ending with tilde.
  1666 
  1667   \<^item> @{system_option_def spell_checker} is a global guard for all spell-checker
  1668   operations: it allows to disable that mechanism altogether.
  1669 
  1670   \<^item> @{system_option_def spell_checker_dictionary} determines the current
  1671   dictionary, taken from the colon-separated list in the settings variable
  1672   @{setting_def JORTHO_DICTIONARIES}. There are jEdit actions to specify local
  1673   updates to a dictionary, by including or excluding words. The result of
  1674   permanent dictionary updates is stored in the directory @{path
  1675   "$ISABELLE_HOME_USER/dictionaries"}, in a separate file for each dictionary.
  1676 
  1677   \<^item> @{system_option_def spell_checker_include} specifies a comma-separated
  1678   list of markup elements that delimit words in the source that is subject to
  1679   spell-checking, including various forms of comments.
  1680 
  1681   \<^item> @{system_option_def spell_checker_exclude} specifies a comma-separated
  1682   list of markup elements that disable spell-checking (e.g.\ in nested
  1683   antiquotations).
  1684 \<close>
  1685 
  1686 
  1687 section \<open>Automatically tried tools \label{sec:auto-tools}\<close>
  1688 
  1689 text \<open>
  1690   Continuous document processing works asynchronously in the background.
  1691   Visible document source that has been evaluated may get augmented by
  1692   additional results of \<^emph>\<open>asynchronous print functions\<close>. An example for that
  1693   is proof state output, if that is enabled in the Output panel
  1694   (\secref{sec:output}). More heavy-weight print functions may be applied as
  1695   well, e.g.\ to prove or disprove parts of the formal text by other means.
  1696 
  1697   Isabelle/HOL provides various automatically tried tools that operate on
  1698   outermost goal statements (e.g.\ @{command lemma}, @{command theorem}),
  1699   independently of the state of the current proof attempt. They work
  1700   implicitly without any arguments. Results are output as \<^emph>\<open>information
  1701   messages\<close>, which are indicated in the text area by blue squiggles and a blue
  1702   information sign in the gutter (see \figref{fig:auto-tools}). The message
  1703   content may be shown as for other output (see also \secref{sec:output}).
  1704   Some tools produce output with \<^emph>\<open>sendback\<close> markup, which means that clicking
  1705   on certain parts of the text inserts that into the source in the proper
  1706   place.
  1707 
  1708   \begin{figure}[!htb]
  1709   \begin{center}
  1710   \includegraphics[scale=0.333]{auto-tools}
  1711   \end{center}
  1712   \caption{Result of automatically tried tools}
  1713   \label{fig:auto-tools}
  1714   \end{figure}
  1715 
  1716   \<^medskip>
  1717   The following Isabelle system options control the behavior of automatically
  1718   tried tools (see also the jEdit dialog window \<^emph>\<open>Plugin Options~/ Isabelle~/
  1719   General~/ Automatically tried tools\<close>):
  1720 
  1721   \<^item> @{system_option_ref auto_methods} controls automatic use of a combination
  1722   of standard proof methods (@{method auto}, @{method simp}, @{method blast},
  1723   etc.). This corresponds to the Isar command @{command_ref "try0"} @{cite
  1724   "isabelle-isar-ref"}.
  1725 
  1726   The tool is disabled by default, since unparameterized invocation of
  1727   standard proof methods often consumes substantial CPU resources without
  1728   leading to success.
  1729 
  1730   \<^item> @{system_option_ref auto_nitpick} controls a slightly reduced version of
  1731   @{command_ref nitpick}, which tests for counterexamples using first-order
  1732   relational logic. See also the Nitpick manual @{cite "isabelle-nitpick"}.
  1733 
  1734   This tool is disabled by default, due to the extra overhead of invoking an
  1735   external Java process for each attempt to disprove a subgoal.
  1736 
  1737   \<^item> @{system_option_ref auto_quickcheck} controls automatic use of
  1738   @{command_ref quickcheck}, which tests for counterexamples using a series of
  1739   assignments for free variables of a subgoal.
  1740 
  1741   This tool is \<^emph>\<open>enabled\<close> by default. It requires little overhead, but is a
  1742   bit weaker than @{command nitpick}.
  1743 
  1744   \<^item> @{system_option_ref auto_sledgehammer} controls a significantly reduced
  1745   version of @{command_ref sledgehammer}, which attempts to prove a subgoal
  1746   using external automatic provers. See also the Sledgehammer manual @{cite
  1747   "isabelle-sledgehammer"}.
  1748 
  1749   This tool is disabled by default, due to the relatively heavy nature of
  1750   Sledgehammer.
  1751 
  1752   \<^item> @{system_option_ref auto_solve_direct} controls automatic use of
  1753   @{command_ref solve_direct}, which checks whether the current subgoals can
  1754   be solved directly by an existing theorem. This also helps to detect
  1755   duplicate lemmas.
  1756 
  1757   This tool is \<^emph>\<open>enabled\<close> by default.
  1758 
  1759 
  1760   Invocation of automatically tried tools is subject to some global policies
  1761   of parallel execution, which may be configured as follows:
  1762 
  1763   \<^item> @{system_option_ref auto_time_limit} (default 2.0) determines the timeout
  1764   (in seconds) for each tool execution.
  1765 
  1766   \<^item> @{system_option_ref auto_time_start} (default 1.0) determines the start
  1767   delay (in seconds) for automatically tried tools, after the main command
  1768   evaluation is finished.
  1769 
  1770 
  1771   Each tool is submitted independently to the pool of parallel execution tasks
  1772   in Isabelle/ML, using hardwired priorities according to its relative
  1773   ``heaviness''. The main stages of evaluation and printing of proof states
  1774   take precedence, but an already running tool is not canceled and may thus
  1775   reduce reactivity of proof document processing.
  1776 
  1777   Users should experiment how the available CPU resources (number of cores)
  1778   are best invested to get additional feedback from prover in the background,
  1779   by using a selection of weaker or stronger tools.
  1780 \<close>
  1781 
  1782 
  1783 section \<open>Sledgehammer \label{sec:sledgehammer}\<close>
  1784 
  1785 text \<open>
  1786   The \<^emph>\<open>Sledgehammer\<close> panel (\figref{fig:sledgehammer}) provides a view on
  1787   some independent execution of the Isar command @{command_ref sledgehammer},
  1788   with process indicator (spinning wheel) and GUI elements for important
  1789   Sledgehammer arguments and options. Any number of Sledgehammer panels may be
  1790   active, according to the standard policies of Dockable Window Management in
  1791   jEdit. Closing such windows also cancels the corresponding prover tasks.
  1792 
  1793   \begin{figure}[!htb]
  1794   \begin{center}
  1795   \includegraphics[scale=0.333]{sledgehammer}
  1796   \end{center}
  1797   \caption{An instance of the Sledgehammer panel}
  1798   \label{fig:sledgehammer}
  1799   \end{figure}
  1800 
  1801   The \<^emph>\<open>Apply\<close> button attaches a fresh invocation of @{command sledgehammer}
  1802   to the command where the cursor is pointing in the text --- this should be
  1803   some pending proof problem. Further buttons like \<^emph>\<open>Cancel\<close> and \<^emph>\<open>Locate\<close>
  1804   help to manage the running process.
  1805 
  1806   Results appear incrementally in the output window of the panel. Proposed
  1807   proof snippets are marked-up as \<^emph>\<open>sendback\<close>, which means a single mouse
  1808   click inserts the text into a suitable place of the original source. Some
  1809   manual editing may be required nonetheless, say to remove earlier proof
  1810   attempts.
  1811 \<close>
  1812 
  1813 
  1814 chapter \<open>Isabelle document preparation\<close>
  1815 
  1816 text \<open>
  1817   The ultimate purpose of Isabelle is to produce nicely rendered documents
  1818   with the Isabelle document preparation system, which is based on {\LaTeX};
  1819   see also @{cite "isabelle-system" and "isabelle-isar-ref"}. Isabelle/jEdit
  1820   provides some additional support for document editing.
  1821 \<close>
  1822 
  1823 
  1824 section \<open>Document outline\<close>
  1825 
  1826 text \<open>
  1827   Theory sources may contain document markup commands, such as @{command_ref
  1828   chapter}, @{command_ref section}, @{command subsection}. The Isabelle
  1829   SideKick parser (\secref{sec:sidekick}) represents this document outline as
  1830   structured tree view, with formal statements and proofs nested inside; see
  1831   \figref{fig:sidekick-document}.
  1832 
  1833   \begin{figure}[!htb]
  1834   \begin{center}
  1835   \includegraphics[scale=0.333]{sidekick-document}
  1836   \end{center}
  1837   \caption{Isabelle document outline via SideKick tree view}
  1838   \label{fig:sidekick-document}
  1839   \end{figure}
  1840 
  1841   It is also possible to use text folding according to this structure, by
  1842   adjusting \<^emph>\<open>Utilities / Buffer Options / Folding mode\<close> of jEdit. The default
  1843   mode \<^verbatim>\<open>isabelle\<close> uses the structure of formal definitions, statements, and
  1844   proofs. The alternative mode \<^verbatim>\<open>sidekick\<close> uses the document structure of the
  1845   SideKick parser, as explained above.
  1846 \<close>
  1847 
  1848 
  1849 section \<open>Markdown structure\<close>
  1850 
  1851 text \<open>
  1852   Document text is internally structured in paragraphs and nested lists, using
  1853   notation that is similar to Markdown\<^footnote>\<open>\<^url>\<open>http://commonmark.org\<close>\<close>. There are
  1854   special control symbols for items of different kinds of lists, corresponding
  1855   to \<^verbatim>\<open>itemize\<close>, \<^verbatim>\<open>enumerate\<close>, \<^verbatim>\<open>description\<close> in {\LaTeX}. This is illustrated
  1856   in for \<^verbatim>\<open>itemize\<close> in \figref{fig:markdown-document}.
  1857 
  1858   \begin{figure}[!htb]
  1859   \begin{center}
  1860   \includegraphics[scale=0.333]{markdown-document}
  1861   \end{center}
  1862   \caption{Markdown structure within document text}
  1863   \label{fig:markdown-document}
  1864   \end{figure}
  1865 
  1866   Items take colour according to the depth of nested lists. This helps to
  1867   explore the implicit rules for list structure interactively. There is also
  1868   markup for individual paragraphs in the text: it may be explored via mouse
  1869   hovering with \<^verbatim>\<open>CONTROL\<close> / \<^verbatim>\<open>COMMAND\<close> as usual
  1870   (\secref{sec:tooltips-hyperlinks}).
  1871 \<close>
  1872 
  1873 
  1874 section \<open>Citations and Bib{\TeX} entries \label{sec:bibtex}\<close>
  1875 
  1876 text \<open>
  1877   Citations are managed by {\LaTeX} and Bib{\TeX} in \<^verbatim>\<open>.bib\<close> files. The
  1878   Isabelle session build process and the @{tool latex} tool @{cite
  1879   "isabelle-system"} are smart enough to assemble the result, based on the
  1880   session directory layout.
  1881 
  1882   The document antiquotation \<open>@{cite}\<close> is described in @{cite
  1883   "isabelle-isar-ref"}. Within the Prover IDE it provides semantic markup for
  1884   tooltips, hyperlinks, and completion for Bib{\TeX} database entries.
  1885   Isabelle/jEdit does \<^emph>\<open>not\<close> know about the actual Bib{\TeX} environment used
  1886   in {\LaTeX} batch-mode, but it can take citations from those \<^verbatim>\<open>.bib\<close> files
  1887   that happen to be open in the editor; see \figref{fig:cite-completion}.
  1888 
  1889   \begin{figure}[!htb]
  1890   \begin{center}
  1891   \includegraphics[scale=0.333]{cite-completion}
  1892   \end{center}
  1893   \caption{Semantic completion of citations from open Bib{\TeX} files}
  1894   \label{fig:cite-completion}
  1895   \end{figure}
  1896 
  1897   Isabelle/jEdit also provides IDE support for editing \<^verbatim>\<open>.bib\<close> files
  1898   themselves. There is syntax highlighting based on entry types (according to
  1899   standard Bib{\TeX} styles), a context-menu to compose entries
  1900   systematically, and a SideKick tree view of the overall content; see
  1901   \figref{fig:bibtex-mode}. Semantic checking with errors and warnings is
  1902   performed by the original \<^verbatim>\<open>bibtex\<close> tool using style \<^verbatim>\<open>plain\<close>: different
  1903   Bib{\TeX} styles may produce slightly different results.
  1904 
  1905   \begin{figure}[!htb]
  1906   \begin{center}
  1907   \includegraphics[scale=0.333]{bibtex-mode}
  1908   \end{center}
  1909   \caption{Bib{\TeX} mode with context menu, SideKick tree view, and
  1910     semantic output from the \<^verbatim>\<open>bibtex\<close> tool}
  1911   \label{fig:bibtex-mode}
  1912   \end{figure}
  1913 
  1914   Regular document preview (\secref{sec:document-preview}) of \<^verbatim>\<open>.bib\<close> files
  1915   approximates the usual {\LaTeX} bibliography output in HTML (using style
  1916   \<^verbatim>\<open>unsort\<close>).
  1917 \<close>
  1918 
  1919 
  1920 section \<open>Document preview \label{sec:document-preview}\<close>
  1921 
  1922 text \<open>
  1923   The action @{action_def isabelle.preview} opens an HTML preview of the
  1924   current document node in the default web browser. The content is derived
  1925   from the semantic markup produced by the prover, and thus depends on the
  1926   status of formal processing.
  1927 
  1928   Action @{action_def isabelle.draft} is similar to @{action
  1929   isabelle.preview}, but shows a plain-text document draft.
  1930 \<close>
  1931 
  1932 
  1933 chapter \<open>ML debugging within the Prover IDE\<close>
  1934 
  1935 text \<open>
  1936   Isabelle/ML is based on Poly/ML\<^footnote>\<open>\<^url>\<open>https://www.polyml.org\<close>\<close> and thus
  1937   benefits from the source-level debugger of that implementation of Standard
  1938   ML. The Prover IDE provides the \<^emph>\<open>Debugger\<close> dockable to connect to running
  1939   ML threads, inspect the stack frame with local ML bindings, and evaluate ML
  1940   expressions in a particular run-time context. A typical debugger session is
  1941   shown in \figref{fig:ml-debugger}.
  1942 
  1943   ML debugging depends on the following pre-requisites.
  1944 
  1945     \<^enum> ML source needs to be compiled with debugging enabled. This may be
  1946     controlled for particular chunks of ML sources using any of the subsequent
  1947     facilities.
  1948 
  1949       \<^enum> The system option @{system_option_ref ML_debugger} as implicit state
  1950       of the Isabelle process. It may be changed in the menu \<^emph>\<open>Plugins /
  1951       Plugin Options / Isabelle / General\<close>. ML modules need to be reloaded and
  1952       recompiled to pick up that option as intended.
  1953 
  1954       \<^enum> The configuration option @{attribute_ref ML_debugger}, with an
  1955       attribute of the same name, to update a global or local context (e.g.\
  1956       with the @{command declare} command).
  1957 
  1958       \<^enum> Commands that modify @{attribute ML_debugger} state for individual
  1959       files: @{command_ref ML_file_debug}, @{command_ref ML_file_no_debug},
  1960       @{command_ref SML_file_debug}, @{command_ref SML_file_no_debug}.
  1961 
  1962     The instrumentation of ML code for debugging causes minor run-time
  1963     overhead. ML modules that implement critical system infrastructure may
  1964     lead to deadlocks or other undefined behaviour, when put under debugger
  1965     control!
  1966 
  1967     \<^enum> The \<^emph>\<open>Debugger\<close> panel needs to be active, otherwise the program ignores
  1968     debugger instrumentation of the compiler and runs unmanaged. It is also
  1969     possible to start debugging with the panel open, and later undock it, to
  1970     let the program continue unhindered.
  1971 
  1972     \<^enum> The ML program needs to be stopped at a suitable breakpoint, which may
  1973     be activated individually or globally as follows.
  1974 
  1975     For ML sources that have been compiled with debugger support, the IDE
  1976     visualizes possible breakpoints in the text. A breakpoint may be toggled
  1977     by pointing accurately with the mouse, with a right-click to activate
  1978     jEdit's context menu and its \<^emph>\<open>Toggle Breakpoint\<close> item. Alternatively, the
  1979     \<^emph>\<open>Break\<close> checkbox in the \<^emph>\<open>Debugger\<close> panel may be enabled to stop ML
  1980     threads always at the next possible breakpoint.
  1981 
  1982   Note that the state of individual breakpoints \<^emph>\<open>gets lost\<close> when the
  1983   coresponding ML source is re-compiled! This may happen unintentionally,
  1984   e.g.\ when following hyperlinks into ML modules that have not been loaded
  1985   into the IDE before.
  1986 
  1987   \begin{figure}[!htb]
  1988   \begin{center}
  1989   \includegraphics[scale=0.333]{ml-debugger}
  1990   \end{center}
  1991   \caption{ML debugger session}
  1992   \label{fig:ml-debugger}
  1993   \end{figure}
  1994 
  1995   The debugger panel (\figref{fig:ml-debugger}) shows a list of all threads
  1996   that are presently stopped. Each thread shows a stack of all function
  1997   invocations that lead to the current breakpoint at the top.
  1998 
  1999   It is possible to jump between stack positions freely, by clicking on this
  2000   list. The current situation is displayed in the big output window, as a
  2001   local ML environment with names and printed values.
  2002 
  2003   ML expressions may be evaluated in the current context by entering snippets
  2004   of source into the text fields labeled \<open>Context\<close> and \<open>ML\<close>, and pushing the
  2005   \<open>Eval\<close> button. By default, the source is interpreted as Isabelle/ML with the
  2006   usual support for antiquotations (like @{command ML}, @{command ML_file}).
  2007   Alternatively, strict Standard ML may be enforced via the \<^emph>\<open>SML\<close> checkbox
  2008   (like @{command SML_file}).
  2009 
  2010   The context for Isabelle/ML is optional, it may evaluate to a value of type
  2011   @{ML_type theory}, @{ML_type Proof.context}, or @{ML_type Context.generic}.
  2012   Thus the given ML expression (with its antiquotations) may be subject to the
  2013   intended dynamic run-time context, instead of the static compile-time
  2014   context.
  2015 
  2016   \<^medskip>
  2017   The buttons labeled \<^emph>\<open>Continue\<close>, \<^emph>\<open>Step\<close>, \<^emph>\<open>Step over\<close>, \<^emph>\<open>Step out\<close>
  2018   recommence execution of the program, with different policies concerning
  2019   nested function invocations. The debugger always moves the cursor within the
  2020   ML source to the next breakpoint position, and offers new stack frames as
  2021   before.
  2022 \<close>
  2023 
  2024 
  2025 chapter \<open>Miscellaneous tools\<close>
  2026 
  2027 section \<open>Timing\<close>
  2028 
  2029 text \<open>
  2030   Managed evaluation of commands within PIDE documents includes timing
  2031   information, which consists of elapsed (wall-clock) time, CPU time, and GC
  2032   (garbage collection) time. Note that in a multithreaded system it is
  2033   difficult to measure execution time precisely: elapsed time is closer to the
  2034   real requirements of runtime resources than CPU or GC time, which are both
  2035   subject to influences from the parallel environment that are outside the
  2036   scope of the current command transaction.
  2037 
  2038   The \<^emph>\<open>Timing\<close> panel provides an overview of cumulative command timings for
  2039   each document node. Commands with elapsed time below the given threshold are
  2040   ignored in the grand total. Nodes are sorted according to their overall
  2041   timing. For the document node that corresponds to the current buffer,
  2042   individual command timings are shown as well. A double-click on a theory
  2043   node or command moves the editor focus to that particular source position.
  2044 
  2045   It is also possible to reveal individual timing information via some tooltip
  2046   for the corresponding command keyword, using the technique of mouse hovering
  2047   with \<^verbatim>\<open>CONTROL\<close>~/ \<^verbatim>\<open>COMMAND\<close> modifier (\secref{sec:tooltips-hyperlinks}).
  2048   Actual display of timing depends on the global option @{system_option_ref
  2049   jedit_timing_threshold}, which can be configured in \<^emph>\<open>Plugin Options~/
  2050   Isabelle~/ General\<close>.
  2051 
  2052   \<^medskip>
  2053   The \<^emph>\<open>Monitor\<close> panel visualizes various data collections about recent
  2054   activity of the Isabelle/ML task farm and the underlying ML runtime system.
  2055   The display is continuously updated according to @{system_option_ref
  2056   editor_chart_delay}. Note that the painting of the chart takes considerable
  2057   runtime itself --- on the Java Virtual Machine that runs Isabelle/Scala, not
  2058   Isabelle/ML. Internally, the Isabelle/Scala module \<^verbatim>\<open>isabelle.ML_Statistics\<close>
  2059   provides further access to statistics of Isabelle/ML.
  2060 \<close>
  2061 
  2062 
  2063 section \<open>Low-level output\<close>
  2064 
  2065 text \<open>
  2066   Prover output is normally shown directly in the main text area or specific
  2067   panels like \<^emph>\<open>Output\<close> (\secref{sec:output}) or \<^emph>\<open>State\<close>
  2068   (\secref{sec:state-output}). Beyond this, it is occasionally useful to
  2069   inspect low-level output channels via some of the following additional
  2070   panels:
  2071 
  2072   \<^item> \<^emph>\<open>Protocol\<close> shows internal messages between the Isabelle/Scala and
  2073   Isabelle/ML side of the PIDE document editing protocol. Recording of
  2074   messages starts with the first activation of the corresponding dockable
  2075   window; earlier messages are lost.
  2076 
  2077   Actual display of protocol messages causes considerable slowdown, so it is
  2078   important to undock all \<^emph>\<open>Protocol\<close> panels for production work.
  2079 
  2080   \<^item> \<^emph>\<open>Raw Output\<close> shows chunks of text from the \<^verbatim>\<open>stdout\<close> and \<^verbatim>\<open>stderr\<close>
  2081   channels of the prover process. Recording of output starts with the first
  2082   activation of the corresponding dockable window; earlier output is lost.
  2083 
  2084   The implicit stateful nature of physical I/O channels makes it difficult to
  2085   relate raw output to the actual command from where it was originating.
  2086   Parallel execution may add to the confusion. Peeking at physical process I/O
  2087   is only the last resort to diagnose problems with tools that are not PIDE
  2088   compliant.
  2089 
  2090   Under normal circumstances, prover output always works via managed message
  2091   channels (corresponding to @{ML writeln}, @{ML warning}, @{ML
  2092   Output.error_message} in Isabelle/ML), which are displayed by regular means
  2093   within the document model (\secref{sec:output}). Unhandled Isabelle/ML
  2094   exceptions are printed by the system via @{ML Output.error_message}.
  2095 
  2096   \<^item> \<^emph>\<open>Syslog\<close> shows system messages that might be relevant to diagnose
  2097   problems with the startup or shutdown phase of the prover process; this also
  2098   includes raw output on \<^verbatim>\<open>stderr\<close>. Isabelle/ML also provides an explicit @{ML
  2099   Output.system_message} operation, which is occasionally useful for
  2100   diagnostic purposes within the system infrastructure itself.
  2101 
  2102   A limited amount of syslog messages are buffered, independently of the
  2103   docking state of the \<^emph>\<open>Syslog\<close> panel. This allows to diagnose serious
  2104   problems with Isabelle/PIDE process management, outside of the actual
  2105   protocol layer.
  2106 
  2107   Under normal situations, such low-level system output can be ignored.
  2108 \<close>
  2109 
  2110 
  2111 chapter \<open>Known problems and workarounds \label{sec:problems}\<close>
  2112 
  2113 text \<open>
  2114   \<^item> \<^bold>\<open>Problem:\<close> Odd behavior of some diagnostic commands with global
  2115   side-effects, like writing a physical file.
  2116 
  2117   \<^bold>\<open>Workaround:\<close> Copy/paste complete command text from elsewhere, or disable
  2118   continuous checking temporarily.
  2119 
  2120   \<^item> \<^bold>\<open>Problem:\<close> Keyboard shortcuts \<^verbatim>\<open>C+PLUS\<close> and \<^verbatim>\<open>C+MINUS\<close> for adjusting the
  2121   editor font size depend on platform details and national keyboards.
  2122 
  2123   \<^bold>\<open>Workaround:\<close> Rebind keys via \<^emph>\<open>Global Options~/ Shortcuts\<close>.
  2124 
  2125   \<^item> \<^bold>\<open>Problem:\<close> The Mac OS X key sequence \<^verbatim>\<open>COMMAND+COMMA\<close> for application
  2126   \<^emph>\<open>Preferences\<close> is in conflict with the jEdit default keyboard shortcut for
  2127   \<^emph>\<open>Incremental Search Bar\<close> (action @{action_ref "quick-search"}).
  2128 
  2129   \<^bold>\<open>Workaround:\<close> Rebind key via \<^emph>\<open>Global Options~/ Shortcuts\<close> according to
  2130   national keyboard, e.g.\ \<^verbatim>\<open>COMMAND+SLASH\<close> on English ones.
  2131 
  2132   \<^item> \<^bold>\<open>Problem:\<close> On Mac OS X with native Apple look-and-feel, some exotic
  2133   national keyboards may cause a conflict of menu accelerator keys with
  2134   regular jEdit key bindings. This leads to duplicate execution of the
  2135   corresponding jEdit action.
  2136 
  2137   \<^bold>\<open>Workaround:\<close> Disable the native Apple menu bar via Java runtime option
  2138   \<^verbatim>\<open>-Dapple.laf.useScreenMenuBar=false\<close>.
  2139 
  2140   \<^item> \<^bold>\<open>Problem:\<close> Mac OS X system fonts sometimes lead to character drop-outs in
  2141   the main text area.
  2142 
  2143   \<^bold>\<open>Workaround:\<close> Use the default \<^verbatim>\<open>Isabelle DejaVu\<close> fonts.
  2144 
  2145   \<^item> \<^bold>\<open>Problem:\<close> Some Linux/X11 input methods such as IBus tend to disrupt key
  2146   event handling of Java/AWT/Swing.
  2147 
  2148   \<^bold>\<open>Workaround:\<close> Do not use X11 input methods. Note that environment variable
  2149   \<^verbatim>\<open>XMODIFIERS\<close> is reset by default within Isabelle settings.
  2150 
  2151   \<^item> \<^bold>\<open>Problem:\<close> Some Linux/X11 window managers that are not ``re-parenting''
  2152   cause problems with additional windows opened by Java. This affects either
  2153   historic or neo-minimalistic window managers like \<^verbatim>\<open>awesome\<close> or \<^verbatim>\<open>xmonad\<close>.
  2154 
  2155   \<^bold>\<open>Workaround:\<close> Use a regular re-parenting X11 window manager.
  2156 
  2157   \<^item> \<^bold>\<open>Problem:\<close> Various forks of Linux/X11 window managers and desktop
  2158   environments (like Gnome) disrupt the handling of menu popups and mouse
  2159   positions of Java/AWT/Swing.
  2160 
  2161   \<^bold>\<open>Workaround:\<close> Use suitable version of Linux desktops.
  2162 
  2163   \<^item> \<^bold>\<open>Problem:\<close> Full-screen mode via jEdit action @{action_ref
  2164   "toggle-full-screen"} (default keyboard shortcut \<^verbatim>\<open>F11\<close>) works on Windows,
  2165   but not on Mac OS X or various Linux/X11 window managers.
  2166 
  2167   \<^bold>\<open>Workaround:\<close> Use native full-screen control of the window manager (notably
  2168   on Mac OS X).
  2169 
  2170   \<^item> \<^bold>\<open>Problem:\<close> Heap space of the JVM may fill up and render the Prover IDE
  2171   unresponsive, e.g.\ when editing big Isabelle sessions with many theories.
  2172 
  2173   \<^bold>\<open>Workaround:\<close> Increase JVM heap parameters by editing platform-specific
  2174   files (for ``properties'' or ``options'') that are associated with the main
  2175   app bundle.
  2176 
  2177   Also note that jEdit provides a heap space monitor in the status line
  2178   (bottom-right). Double-clicking on that causes full garbage-collection,
  2179   which sometimes helps in low-memory situations.
  2180 \<close>
  2181 
  2182 end