diff -r 2e2a506553a3 -r af7239e3054d doc-src/TutorialI/basics.tex --- a/doc-src/TutorialI/basics.tex Fri Jun 10 17:59:12 2005 +0200 +++ b/doc-src/TutorialI/basics.tex Fri Jun 10 18:36:47 2005 +0200 @@ -87,10 +87,10 @@ \begin{center}\small \url{http://isabelle.in.tum.de/library/HOL/} \end{center} -and is recommended browsing. -There is also a growing Library~\cite{HOL-Library}\index{Library} -of useful theories that are not part of \isa{Main} but can be included -among the parents of a theory and will then be loaded automatically. +and is recommended browsing. In subdirectory \texttt{Library} you find +a growing library of useful theories that are not part of \isa{Main} +but can be included among the parents of a theory and will then be +loaded automatically. For the more adventurous, there is the \emph{Archive of Formal Proofs}, a journal-like collection of more advanced Isabelle theories: @@ -134,15 +134,17 @@ \end{description} \begin{warn} Types are extremely important because they prevent us from writing - nonsense. Isabelle insists that all terms and formulae must be well-typed - and will print an error message if a type mismatch is encountered. To - reduce the amount of explicit type information that needs to be provided by - the user, Isabelle infers the type of all variables automatically (this is - called \bfindex{type inference}) and keeps quiet about it. Occasionally - this may lead to misunderstandings between you and the system. If anything - strange happens, we recommend that you ask Isabelle to display all type - information. This is best done through the Proof General interface; see - \S\ref{sec:interface} for details. + nonsense. Isabelle insists that all terms and formulae must be + well-typed and will print an error message if a type mismatch is + encountered. To reduce the amount of explicit type information that + needs to be provided by the user, Isabelle infers the type of all + variables automatically (this is called \bfindex{type inference}) + and keeps quiet about it. Occasionally this may lead to + misunderstandings between you and the system. If anything strange + happens, we recommend that you ask Isabelle to display all type + information via the Proof General menu item \textsf{Isabelle} $>$ + \textsf{Settings} $>$ \textsf{Show Types} (see \S\ref{sec:interface} + for details). \end{warn}% \index{types|)} @@ -257,16 +259,13 @@ the appendix. \begin{warn} -A particular -problem for novices can be the priority of operators. If you are unsure, use -additional parentheses. In those cases where Isabelle echoes your -input, you can see which parentheses are dropped --- they were superfluous. If -you are unsure how to interpret Isabelle's output because you don't know -where the (dropped) parentheses go, set the flag\index{flags} -\isa{show_brackets}\index{*show_brackets (flag)}: -\begin{ttbox} -ML "set show_brackets"; \(\dots\); ML "reset show_brackets"; -\end{ttbox} +A particular problem for novices can be the priority of operators. If +you are unsure, use additional parentheses. In those cases where +Isabelle echoes your input, you can see which parentheses are dropped +--- they were superfluous. If you are unsure how to interpret +Isabelle's output because you don't know where the (dropped) +parentheses go, set the Proof General flag \textsf{Isabelle} $>$ +\textsf{Settings} $>$ \textsf{Show Brackets} (see \S\ref{sec:interface}). \end{warn} @@ -304,48 +303,52 @@ \section{Interaction and Interfaces} \label{sec:interface} -Interaction with Isabelle can either occur at the shell level or through more -advanced interfaces. To keep the tutorial independent of the interface, we -have phrased the description of the interaction in a neutral language. For -example, the phrase ``to abandon a proof'' means to type \isacommand{oops} at the -shell level, which is explained the first time the phrase is used. Other -interfaces perform the same act by cursor movements and/or mouse clicks. -Although shell-based interaction is quite feasible for the kind of proof -scripts currently presented in this tutorial, the recommended interface for -Isabelle/Isar is the Emacs-based \bfindex{Proof - General}~\cite{proofgeneral,Aspinall:TACAS:2000}. +The recommended interface for Isabelle/Isar is the (X)Emacs-based +\bfindex{Proof General}~\cite{proofgeneral,Aspinall:TACAS:2000}. +Interaction with Isabelle at the shell level, although possible, +should be avoided. Most of the tutorial is independent of the +interface and is phrased in a neutral language. For example, the +phrase ``to abandon a proof'' corresponds to the obvious +action of clicking on the \textsf{Undo} symbol in Proof General. +Proof General specific information is often displayed in paragraphs +identified by a miniature Proof General icon. Here are two examples: +\begin{pgnote} +Proof General supports a special font with mathematical symbols known +as ``x-symbols''. All symbols have \textsc{ascii}-equivalents: for +example, you can enter either \verb!&! or \verb!\! to obtain +$\land$. For a list of the most frequent symbols see table~\ref{tab:ascii} +in the appendix. -\begin{pgnote} -Proof General specific information is always displayed in paragraphs -identified by this miniature Proof General icon. - -On particularly nice feature of Proof General is its support for a special -fonts with mathematical symbols. Most symbols have -\textsc{ascii}-equivalents: for example, you can enter either \verb!&! -or \verb!\! to obtain $\land$. For a list of the most frequent symbols -see table~\ref{tab:ascii} in the appendix. +Note that by default x-symbols are not enabled. You have to switch +them on via the menu item \textsf{Proof-General} $>$ \textsf{Options} $>$ +\textsf{X-Symbols} (and save the option via the top-level +\textsf{Options} menu). \end{pgnote} \begin{pgnote} -Proof General offers an \texttt{Isabelle} menu for displaying information -and setting flags. A particularly useful flag is \texttt{Show Types} -which causes Isabelle to output the type information that is usually +Proof General offers the \textsf{Isabelle} menu for displaying +information and setting flags. A particularly useful flag is +\textsf{Isabelle} $>$ \textsf{Settings} $>$ \textsf{Show Types} which +causes Isabelle to output the type information that is usually suppressed. This is indispensible in case of errors of all kinds -because often the types reveal the source of the problem. Once you have -diagnosed the problem you may no longer want to see the types because they -clutter all output. Simply reset the flag. +because often the types reveal the source of the problem. Once you +have diagnosed the problem you may no longer want to see the types +because they clutter all output. Simply reset the flag. \end{pgnote} \section{Getting Started} -Assuming you have installed Isabelle, you start it by typing \texttt{isabelle - -I HOL} in a shell window.\footnote{Simply executing \texttt{isabelle -I} - starts the default logic, which usually is already \texttt{HOL}. This is - controlled by the \texttt{ISABELLE_LOGIC} setting, see \emph{The Isabelle - System Manual} for more details.} This presents you with Isabelle's most -basic \textsc{ascii} interface. In addition you need to open an editor window to -create theory files. While you are developing a theory, we recommend that you -type each command into the file first and then enter it into Isabelle by -copy-and-paste, thus ensuring that you have a complete record of your theory. -As mentioned above, Proof General offers a much superior interface. -If you have installed Proof General, you can start it by typing \texttt{Isabelle}. +Assuming you have installed Isabelle and Proof General, you start it by typing +\texttt{Isabelle} in a shell window. This launches a Proof General window. +By default, you are in HOL\footnote{This is controlled by the +\texttt{ISABELLE_LOGIC} setting, see \emph{The Isabelle System Manual} +for more details.}. + +\begin{pgnote} +You can choose a different logic via the \textsf{Isabelle} $>$ +\textsf{Logics} menu. For example, you may want to work in the real +numbers, an extension of HOL (see \S\ref{sec:real}). +% This is just excess baggage: +%(You have to restart Proof General if you only compile the new logic +%after having launching Proof General already). +\end{pgnote}