| author | wenzelm |
| Thu, 08 May 2008 22:20:33 +0200 | |
| changeset 26854 | 9b4aec46ad78 |
| parent 26852 | a31203f58b20 |
| child 26861 | e6fe036ec21d |
| permissions | -rw-r--r-- |
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\begin{isabellebody}%
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\def\isabellecontext{HOL{\isacharunderscore}Specific}%
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% |
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\isadelimtheory |
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\isanewline |
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\isanewline |
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\endisadelimtheory |
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\isatagtheory |
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\isacommand{theory}\isamarkupfalse%
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\ HOL{\isacharunderscore}Specific\isanewline
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\isakeyword{imports}\ Main\isanewline
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\isakeyword{begin}%
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\endisatagtheory |
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{\isafoldtheory}%
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% |
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\isadelimtheory |
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\endisadelimtheory |
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% |
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\isamarkupchapter{Isabelle/HOL \label{ch:hol}%
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} |
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\isamarkuptrue% |
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% |
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\isamarkupsection{Primitive types \label{sec:hol-typedef}%
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} |
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\isamarkuptrue% |
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% |
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\begin{isamarkuptext}%
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\begin{matharray}{rcl}
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\indexdef{HOL}{command}{typedecl}\mbox{\isa{\isacommand{typedecl}}} & : & \isartrans{theory}{theory} \\
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\indexdef{HOL}{command}{typedef}\mbox{\isa{\isacommand{typedef}}} & : & \isartrans{theory}{proof(prove)} \\
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\end{matharray}
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\begin{rail}
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'typedecl' typespec infix? |
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; |
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'typedef' altname? abstype '=' repset |
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; |
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altname: '(' (name | 'open' | 'open' name) ')'
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; |
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abstype: typespec infix? |
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; |
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repset: term ('morphisms' name name)?
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; |
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\end{rail}
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\begin{descr}
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\item [\mbox{\isa{\isacommand{typedecl}}}~\isa{{\isachardoublequote}{\isacharparenleft}{\isasymalpha}\isactrlsub {\isadigit{1}}{\isacharcomma}\ {\isasymdots}{\isacharcomma}\ {\isasymalpha}\isactrlsub n{\isacharparenright}\ t{\isachardoublequote}}] is similar to the original \mbox{\isa{\isacommand{typedecl}}} of
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Isabelle/Pure (see \secref{sec:types-pure}), but also declares type
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arity \isa{{\isachardoublequote}t\ {\isacharcolon}{\isacharcolon}\ {\isacharparenleft}type{\isacharcomma}\ {\isasymdots}{\isacharcomma}\ type{\isacharparenright}\ type{\isachardoublequote}}, making \isa{t} an
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actual HOL type constructor. %FIXME check, update |
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\item [\mbox{\isa{\isacommand{typedef}}}~\isa{{\isachardoublequote}{\isacharparenleft}{\isasymalpha}\isactrlsub {\isadigit{1}}{\isacharcomma}\ {\isasymdots}{\isacharcomma}\ {\isasymalpha}\isactrlsub n{\isacharparenright}\ t\ {\isacharequal}\ A{\isachardoublequote}}] sets up a goal stating non-emptiness of the set \isa{A}.
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After finishing the proof, the theory will be augmented by a |
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Gordon/HOL-style type definition, which establishes a bijection |
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between the representing set \isa{A} and the new type \isa{t}.
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Technically, \mbox{\isa{\isacommand{typedef}}} defines both a type \isa{t} and a set (term constant) of the same name (an alternative base
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name may be given in parentheses). The injection from type to set |
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is called \isa{Rep{\isacharunderscore}t}, its inverse \isa{Abs{\isacharunderscore}t} (this may be
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changed via an explicit \mbox{\isa{\isakeyword{morphisms}}} declaration).
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Theorems \isa{Rep{\isacharunderscore}t}, \isa{Rep{\isacharunderscore}t{\isacharunderscore}inverse}, and \isa{Abs{\isacharunderscore}t{\isacharunderscore}inverse} provide the most basic characterization as a
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corresponding injection/surjection pair (in both directions). Rules |
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\isa{Rep{\isacharunderscore}t{\isacharunderscore}inject} and \isa{Abs{\isacharunderscore}t{\isacharunderscore}inject} provide a slightly
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more convenient view on the injectivity part, suitable for automated |
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proof tools (e.g.\ in \mbox{\isa{simp}} or \mbox{\isa{iff}} declarations).
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Rules \isa{Rep{\isacharunderscore}t{\isacharunderscore}cases}/\isa{Rep{\isacharunderscore}t{\isacharunderscore}induct}, and \isa{Abs{\isacharunderscore}t{\isacharunderscore}cases}/\isa{Abs{\isacharunderscore}t{\isacharunderscore}induct} provide alternative views on
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surjectivity; these are already declared as set or type rules for |
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the generic \mbox{\isa{cases}} and \mbox{\isa{induct}} methods.
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An alternative name may be specified in parentheses; the default is |
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to use \isa{t} as indicated before. The ``\isa{{\isachardoublequote}{\isacharparenleft}open{\isacharparenright}{\isachardoublequote}}''
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declaration suppresses a separate constant definition for the |
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representing set. |
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\end{descr}
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Note that raw type declarations are rarely used in practice; the |
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main application is with experimental (or even axiomatic!) theory |
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fragments. Instead of primitive HOL type definitions, user-level |
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theories usually refer to higher-level packages such as \mbox{\isa{\isacommand{record}}} (see \secref{sec:hol-record}) or \mbox{\isa{\isacommand{datatype}}} (see \secref{sec:hol-datatype}).%
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\end{isamarkuptext}%
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\isamarkuptrue% |
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\isamarkupsection{Adhoc tuples%
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} |
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\isamarkuptrue% |
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% |
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\begin{isamarkuptext}%
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\begin{matharray}{rcl}
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\mbox{\isa{split{\isacharunderscore}format}}\isa{{\isachardoublequote}\isactrlsup {\isacharasterisk}{\isachardoublequote}} & : & \isaratt \\
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\end{matharray}
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\begin{rail}
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'split\_format' (((name *) + 'and') | ('(' 'complete' ')'))
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; |
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\end{rail}
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\begin{descr}
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\item [\mbox{\isa{split{\isacharunderscore}format}}~\isa{{\isachardoublequote}p\isactrlsub {\isadigit{1}}\ {\isasymdots}\ p\isactrlsub m\ {\isasymAND}\ {\isasymdots}\ {\isasymAND}\ q\isactrlsub {\isadigit{1}}\ {\isasymdots}\ q\isactrlsub n{\isachardoublequote}}] puts expressions of
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low-level tuple types into canonical form as specified by the |
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arguments given; the \isa{i}-th collection of arguments refers to
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occurrences in premise \isa{i} of the rule. The ``\isa{{\isachardoublequote}{\isacharparenleft}complete{\isacharparenright}{\isachardoublequote}}'' option causes \emph{all} arguments in function
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applications to be represented canonically according to their tuple |
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type structure. |
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Note that these operations tend to invent funny names for new local |
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parameters to be introduced. |
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\end{descr}%
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\end{isamarkuptext}%
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\isamarkuptrue% |
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% |
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\isamarkupsection{Records \label{sec:hol-record}%
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} |
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\isamarkuptrue% |
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% |
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\begin{isamarkuptext}%
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In principle, records merely generalize the concept of tuples, where |
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components may be addressed by labels instead of just position. The |
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logical infrastructure of records in Isabelle/HOL is slightly more |
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advanced, though, supporting truly extensible record schemes. This |
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admits operations that are polymorphic with respect to record |
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extension, yielding ``object-oriented'' effects like (single) |
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inheritance. See also \cite{NaraschewskiW-TPHOLs98} for more
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details on object-oriented verification and record subtyping in HOL.% |
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\end{isamarkuptext}%
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\isamarkuptrue% |
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% |
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\isamarkupsubsection{Basic concepts%
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} |
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\isamarkuptrue% |
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% |
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\begin{isamarkuptext}%
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Isabelle/HOL supports both \emph{fixed} and \emph{schematic} records
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at the level of terms and types. The notation is as follows: |
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\begin{center}
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\begin{tabular}{l|l|l}
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& record terms & record types \\ \hline |
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fixed & \isa{{\isachardoublequote}{\isasymlparr}x\ {\isacharequal}\ a{\isacharcomma}\ y\ {\isacharequal}\ b{\isasymrparr}{\isachardoublequote}} & \isa{{\isachardoublequote}{\isasymlparr}x\ {\isacharcolon}{\isacharcolon}\ A{\isacharcomma}\ y\ {\isacharcolon}{\isacharcolon}\ B{\isasymrparr}{\isachardoublequote}} \\
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schematic & \isa{{\isachardoublequote}{\isasymlparr}x\ {\isacharequal}\ a{\isacharcomma}\ y\ {\isacharequal}\ b{\isacharcomma}\ {\isasymdots}\ {\isacharequal}\ m{\isasymrparr}{\isachardoublequote}} &
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\isa{{\isachardoublequote}{\isasymlparr}x\ {\isacharcolon}{\isacharcolon}\ A{\isacharcomma}\ y\ {\isacharcolon}{\isacharcolon}\ B{\isacharcomma}\ {\isasymdots}\ {\isacharcolon}{\isacharcolon}\ M{\isasymrparr}{\isachardoublequote}} \\
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\end{tabular}
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\end{center}
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\noindent The ASCII representation of \isa{{\isachardoublequote}{\isasymlparr}x\ {\isacharequal}\ a{\isasymrparr}{\isachardoublequote}} is \isa{{\isachardoublequote}{\isacharparenleft}{\isacharbar}\ x\ {\isacharequal}\ a\ {\isacharbar}{\isacharparenright}{\isachardoublequote}}.
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A fixed record \isa{{\isachardoublequote}{\isasymlparr}x\ {\isacharequal}\ a{\isacharcomma}\ y\ {\isacharequal}\ b{\isasymrparr}{\isachardoublequote}} has field \isa{x} of value
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\isa{a} and field \isa{y} of value \isa{b}. The corresponding
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type is \isa{{\isachardoublequote}{\isasymlparr}x\ {\isacharcolon}{\isacharcolon}\ A{\isacharcomma}\ y\ {\isacharcolon}{\isacharcolon}\ B{\isasymrparr}{\isachardoublequote}}, assuming that \isa{{\isachardoublequote}a\ {\isacharcolon}{\isacharcolon}\ A{\isachardoublequote}}
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and \isa{{\isachardoublequote}b\ {\isacharcolon}{\isacharcolon}\ B{\isachardoublequote}}.
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A record scheme like \isa{{\isachardoublequote}{\isasymlparr}x\ {\isacharequal}\ a{\isacharcomma}\ y\ {\isacharequal}\ b{\isacharcomma}\ {\isasymdots}\ {\isacharequal}\ m{\isasymrparr}{\isachardoublequote}} contains fields
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\isa{x} and \isa{y} as before, but also possibly further fields
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as indicated by the ``\isa{{\isachardoublequote}{\isasymdots}{\isachardoublequote}}'' notation (which is actually part
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of the syntax). The improper field ``\isa{{\isachardoublequote}{\isasymdots}{\isachardoublequote}}'' of a record
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scheme is called the \emph{more part}. Logically it is just a free
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variable, which is occasionally referred to as ``row variable'' in |
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the literature. The more part of a record scheme may be |
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instantiated by zero or more further components. For example, the |
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previous scheme may get instantiated to \isa{{\isachardoublequote}{\isasymlparr}x\ {\isacharequal}\ a{\isacharcomma}\ y\ {\isacharequal}\ b{\isacharcomma}\ z\ {\isacharequal}\ c{\isacharcomma}\ {\isasymdots}\ {\isacharequal}\ m{\isacharprime}{\isasymrparr}{\isachardoublequote}}, where \isa{m{\isacharprime}} refers to a different more part.
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Fixed records are special instances of record schemes, where |
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``\isa{{\isachardoublequote}{\isasymdots}{\isachardoublequote}}'' is properly terminated by the \isa{{\isachardoublequote}{\isacharparenleft}{\isacharparenright}\ {\isacharcolon}{\isacharcolon}\ unit{\isachardoublequote}}
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element. In fact, \isa{{\isachardoublequote}{\isasymlparr}x\ {\isacharequal}\ a{\isacharcomma}\ y\ {\isacharequal}\ b{\isasymrparr}{\isachardoublequote}} is just an abbreviation
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for \isa{{\isachardoublequote}{\isasymlparr}x\ {\isacharequal}\ a{\isacharcomma}\ y\ {\isacharequal}\ b{\isacharcomma}\ {\isasymdots}\ {\isacharequal}\ {\isacharparenleft}{\isacharparenright}{\isasymrparr}{\isachardoublequote}}.
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\medskip Two key observations make extensible records in a simply |
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typed language like HOL work out: |
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\begin{enumerate}
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\item the more part is internalized, as a free term or type |
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variable, |
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\item field names are externalized, they cannot be accessed within |
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the logic as first-class values. |
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\end{enumerate}
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\medskip In Isabelle/HOL record types have to be defined explicitly, |
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fixing their field names and types, and their (optional) parent |
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record. Afterwards, records may be formed using above syntax, while |
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obeying the canonical order of fields as given by their declaration. |
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The record package provides several standard operations like |
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selectors and updates. The common setup for various generic proof |
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tools enable succinct reasoning patterns. See also the Isabelle/HOL |
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tutorial \cite{isabelle-hol-book} for further instructions on using
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records in practice.% |
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\end{isamarkuptext}%
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\isamarkuptrue% |
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% |
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\isamarkupsubsection{Record specifications%
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} |
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\isamarkuptrue% |
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% |
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\begin{isamarkuptext}%
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\begin{matharray}{rcl}
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\indexdef{HOL}{command}{record}\mbox{\isa{\isacommand{record}}} & : & \isartrans{theory}{theory} \\
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\end{matharray}
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\begin{rail}
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'record' typespec '=' (type '+')? (constdecl +) |
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; |
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\end{rail}
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\begin{descr}
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\item [\mbox{\isa{\isacommand{record}}}~\isa{{\isachardoublequote}{\isacharparenleft}{\isasymalpha}\isactrlsub {\isadigit{1}}{\isacharcomma}\ {\isasymdots}{\isacharcomma}\ {\isasymalpha}\isactrlsub m{\isacharparenright}\ t\ {\isacharequal}\ {\isasymtau}\ {\isacharplus}\ c\isactrlsub {\isadigit{1}}\ {\isacharcolon}{\isacharcolon}\ {\isasymsigma}\isactrlsub {\isadigit{1}}\ {\isasymdots}\ c\isactrlsub n\ {\isacharcolon}{\isacharcolon}\ {\isasymsigma}\isactrlsub n{\isachardoublequote}}] defines
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extensible record type \isa{{\isachardoublequote}{\isacharparenleft}{\isasymalpha}\isactrlsub {\isadigit{1}}{\isacharcomma}\ {\isasymdots}{\isacharcomma}\ {\isasymalpha}\isactrlsub m{\isacharparenright}\ t{\isachardoublequote}},
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derived from the optional parent record \isa{{\isachardoublequote}{\isasymtau}{\isachardoublequote}} by adding new
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field components \isa{{\isachardoublequote}c\isactrlsub i\ {\isacharcolon}{\isacharcolon}\ {\isasymsigma}\isactrlsub i{\isachardoublequote}} etc.
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The type variables of \isa{{\isachardoublequote}{\isasymtau}{\isachardoublequote}} and \isa{{\isachardoublequote}{\isasymsigma}\isactrlsub i{\isachardoublequote}} need to be
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covered by the (distinct) parameters \isa{{\isachardoublequote}{\isasymalpha}\isactrlsub {\isadigit{1}}{\isacharcomma}\ {\isasymdots}{\isacharcomma}\ {\isasymalpha}\isactrlsub m{\isachardoublequote}}. Type constructor \isa{t} has to be new, while \isa{{\isasymtau}} needs to specify an instance of an existing record type. At
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least one new field \isa{{\isachardoublequote}c\isactrlsub i{\isachardoublequote}} has to be specified.
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Basically, field names need to belong to a unique record. This is |
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not a real restriction in practice, since fields are qualified by |
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the record name internally. |
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The parent record specification \isa{{\isasymtau}} is optional; if omitted
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\isa{t} becomes a root record. The hierarchy of all records
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declared within a theory context forms a forest structure, i.e.\ a |
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set of trees starting with a root record each. There is no way to |
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merge multiple parent records! |
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For convenience, \isa{{\isachardoublequote}{\isacharparenleft}{\isasymalpha}\isactrlsub {\isadigit{1}}{\isacharcomma}\ {\isasymdots}{\isacharcomma}\ {\isasymalpha}\isactrlsub m{\isacharparenright}\ t{\isachardoublequote}} is made a
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type abbreviation for the fixed record type \isa{{\isachardoublequote}{\isasymlparr}c\isactrlsub {\isadigit{1}}\ {\isacharcolon}{\isacharcolon}\ {\isasymsigma}\isactrlsub {\isadigit{1}}{\isacharcomma}\ {\isasymdots}{\isacharcomma}\ c\isactrlsub n\ {\isacharcolon}{\isacharcolon}\ {\isasymsigma}\isactrlsub n{\isasymrparr}{\isachardoublequote}}, likewise is \isa{{\isachardoublequote}{\isacharparenleft}{\isasymalpha}\isactrlsub {\isadigit{1}}{\isacharcomma}\ {\isasymdots}{\isacharcomma}\ {\isasymalpha}\isactrlsub m{\isacharcomma}\ {\isasymzeta}{\isacharparenright}\ t{\isacharunderscore}scheme{\isachardoublequote}} made an abbreviation for
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\isa{{\isachardoublequote}{\isasymlparr}c\isactrlsub {\isadigit{1}}\ {\isacharcolon}{\isacharcolon}\ {\isasymsigma}\isactrlsub {\isadigit{1}}{\isacharcomma}\ {\isasymdots}{\isacharcomma}\ c\isactrlsub n\ {\isacharcolon}{\isacharcolon}\ {\isasymsigma}\isactrlsub n{\isacharcomma}\ {\isasymdots}\ {\isacharcolon}{\isacharcolon}\ {\isasymzeta}{\isasymrparr}{\isachardoublequote}}.
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\end{descr}%
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\end{isamarkuptext}%
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\isamarkuptrue% |
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% |
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\isamarkupsubsection{Record operations%
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} |
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\isamarkuptrue% |
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% |
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\begin{isamarkuptext}%
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Any record definition of the form presented above produces certain |
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standard operations. Selectors and updates are provided for any |
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field, including the improper one ``\isa{more}''. There are also
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cumulative record constructor functions. To simplify the |
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presentation below, we assume for now that \isa{{\isachardoublequote}{\isacharparenleft}{\isasymalpha}\isactrlsub {\isadigit{1}}{\isacharcomma}\ {\isasymdots}{\isacharcomma}\ {\isasymalpha}\isactrlsub m{\isacharparenright}\ t{\isachardoublequote}} is a root record with fields \isa{{\isachardoublequote}c\isactrlsub {\isadigit{1}}\ {\isacharcolon}{\isacharcolon}\ {\isasymsigma}\isactrlsub {\isadigit{1}}{\isacharcomma}\ {\isasymdots}{\isacharcomma}\ c\isactrlsub n\ {\isacharcolon}{\isacharcolon}\ {\isasymsigma}\isactrlsub n{\isachardoublequote}}.
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\medskip \textbf{Selectors} and \textbf{updates} are available for
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any field (including ``\isa{more}''):
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\begin{matharray}{lll}
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\isa{{\isachardoublequote}c\isactrlsub i{\isachardoublequote}} & \isa{{\isachardoublequote}{\isacharcolon}{\isacharcolon}{\isachardoublequote}} & \isa{{\isachardoublequote}{\isasymlparr}\isactrlvec c\ {\isacharcolon}{\isacharcolon}\ \isactrlvec {\isasymsigma}{\isacharcomma}\ {\isasymdots}\ {\isacharcolon}{\isacharcolon}\ {\isasymzeta}{\isasymrparr}\ {\isasymRightarrow}\ {\isasymsigma}\isactrlsub i{\isachardoublequote}} \\
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\isa{{\isachardoublequote}c\isactrlsub i{\isacharunderscore}update{\isachardoublequote}} & \isa{{\isachardoublequote}{\isacharcolon}{\isacharcolon}{\isachardoublequote}} & \isa{{\isachardoublequote}{\isasymsigma}\isactrlsub i\ {\isasymRightarrow}\ {\isasymlparr}\isactrlvec c\ {\isacharcolon}{\isacharcolon}\ \isactrlvec {\isasymsigma}{\isacharcomma}\ {\isasymdots}\ {\isacharcolon}{\isacharcolon}\ {\isasymzeta}{\isasymrparr}\ {\isasymRightarrow}\ {\isasymlparr}\isactrlvec c\ {\isacharcolon}{\isacharcolon}\ \isactrlvec {\isasymsigma}{\isacharcomma}\ {\isasymdots}\ {\isacharcolon}{\isacharcolon}\ {\isasymzeta}{\isasymrparr}{\isachardoublequote}} \\
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\end{matharray}
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There is special syntax for application of updates: \isa{{\isachardoublequote}r{\isasymlparr}x\ {\isacharcolon}{\isacharequal}\ a{\isasymrparr}{\isachardoublequote}} abbreviates term \isa{{\isachardoublequote}x{\isacharunderscore}update\ a\ r{\isachardoublequote}}. Further notation for
|
|
262 |
repeated updates is also available: \isa{{\isachardoublequote}r{\isasymlparr}x\ {\isacharcolon}{\isacharequal}\ a{\isasymrparr}{\isasymlparr}y\ {\isacharcolon}{\isacharequal}\ b{\isasymrparr}{\isasymlparr}z\ {\isacharcolon}{\isacharequal}\ c{\isasymrparr}{\isachardoublequote}} may be written \isa{{\isachardoublequote}r{\isasymlparr}x\ {\isacharcolon}{\isacharequal}\ a{\isacharcomma}\ y\ {\isacharcolon}{\isacharequal}\ b{\isacharcomma}\ z\ {\isacharcolon}{\isacharequal}\ c{\isasymrparr}{\isachardoublequote}}. Note that
|
|
263 |
because of postfix notation the order of fields shown here is |
|
264 |
reverse than in the actual term. Since repeated updates are just |
|
265 |
function applications, fields may be freely permuted in \isa{{\isachardoublequote}{\isasymlparr}x\ {\isacharcolon}{\isacharequal}\ a{\isacharcomma}\ y\ {\isacharcolon}{\isacharequal}\ b{\isacharcomma}\ z\ {\isacharcolon}{\isacharequal}\ c{\isasymrparr}{\isachardoublequote}}, as far as logical equality is concerned.
|
|
266 |
Thus commutativity of independent updates can be proven within the |
|
267 |
logic for any two fields, but not as a general theorem. |
|
268 |
||
269 |
\medskip The \textbf{make} operation provides a cumulative record
|
|
270 |
constructor function: |
|
271 |
||
272 |
\begin{matharray}{lll}
|
|
| 26852 | 273 |
\isa{{\isachardoublequote}t{\isachardot}make{\isachardoublequote}} & \isa{{\isachardoublequote}{\isacharcolon}{\isacharcolon}{\isachardoublequote}} & \isa{{\isachardoublequote}{\isasymsigma}\isactrlsub {\isadigit{1}}\ {\isasymRightarrow}\ {\isasymdots}\ {\isasymsigma}\isactrlsub n\ {\isasymRightarrow}\ {\isasymlparr}\isactrlvec c\ {\isacharcolon}{\isacharcolon}\ \isactrlvec {\isasymsigma}{\isasymrparr}{\isachardoublequote}} \\
|
| 26849 | 274 |
\end{matharray}
|
275 |
||
276 |
\medskip We now reconsider the case of non-root records, which are |
|
277 |
derived of some parent. In general, the latter may depend on |
|
278 |
another parent as well, resulting in a list of \emph{ancestor
|
|
279 |
records}. Appending the lists of fields of all ancestors results in |
|
280 |
a certain field prefix. The record package automatically takes care |
|
281 |
of this by lifting operations over this context of ancestor fields. |
|
282 |
Assuming that \isa{{\isachardoublequote}{\isacharparenleft}{\isasymalpha}\isactrlsub {\isadigit{1}}{\isacharcomma}\ {\isasymdots}{\isacharcomma}\ {\isasymalpha}\isactrlsub m{\isacharparenright}\ t{\isachardoublequote}} has ancestor
|
|
283 |
fields \isa{{\isachardoublequote}b\isactrlsub {\isadigit{1}}\ {\isacharcolon}{\isacharcolon}\ {\isasymrho}\isactrlsub {\isadigit{1}}{\isacharcomma}\ {\isasymdots}{\isacharcomma}\ b\isactrlsub k\ {\isacharcolon}{\isacharcolon}\ {\isasymrho}\isactrlsub k{\isachardoublequote}},
|
|
284 |
the above record operations will get the following types: |
|
285 |
||
| 26852 | 286 |
\medskip |
287 |
\begin{tabular}{lll}
|
|
288 |
\isa{{\isachardoublequote}c\isactrlsub i{\isachardoublequote}} & \isa{{\isachardoublequote}{\isacharcolon}{\isacharcolon}{\isachardoublequote}} & \isa{{\isachardoublequote}{\isasymlparr}\isactrlvec b\ {\isacharcolon}{\isacharcolon}\ \isactrlvec {\isasymrho}{\isacharcomma}\ \isactrlvec c\ {\isacharcolon}{\isacharcolon}\ \isactrlvec {\isasymsigma}{\isacharcomma}\ {\isasymdots}\ {\isacharcolon}{\isacharcolon}\ {\isasymzeta}{\isasymrparr}\ {\isasymRightarrow}\ {\isasymsigma}\isactrlsub i{\isachardoublequote}} \\
|
|
289 |
\isa{{\isachardoublequote}c\isactrlsub i{\isacharunderscore}update{\isachardoublequote}} & \isa{{\isachardoublequote}{\isacharcolon}{\isacharcolon}{\isachardoublequote}} & \isa{{\isachardoublequote}{\isasymsigma}\isactrlsub i\ {\isasymRightarrow}\ {\isasymlparr}\isactrlvec b\ {\isacharcolon}{\isacharcolon}\ \isactrlvec {\isasymrho}{\isacharcomma}\ \isactrlvec c\ {\isacharcolon}{\isacharcolon}\ \isactrlvec {\isasymsigma}{\isacharcomma}\ {\isasymdots}\ {\isacharcolon}{\isacharcolon}\ {\isasymzeta}{\isasymrparr}\ {\isasymRightarrow}\ {\isasymlparr}\isactrlvec b\ {\isacharcolon}{\isacharcolon}\ \isactrlvec {\isasymrho}{\isacharcomma}\ \isactrlvec c\ {\isacharcolon}{\isacharcolon}\ \isactrlvec {\isasymsigma}{\isacharcomma}\ {\isasymdots}\ {\isacharcolon}{\isacharcolon}\ {\isasymzeta}{\isasymrparr}{\isachardoublequote}} \\
|
|
290 |
\isa{{\isachardoublequote}t{\isachardot}make{\isachardoublequote}} & \isa{{\isachardoublequote}{\isacharcolon}{\isacharcolon}{\isachardoublequote}} & \isa{{\isachardoublequote}{\isasymrho}\isactrlsub {\isadigit{1}}\ {\isasymRightarrow}\ {\isasymdots}\ {\isasymrho}\isactrlsub k\ {\isasymRightarrow}\ {\isasymsigma}\isactrlsub {\isadigit{1}}\ {\isasymRightarrow}\ {\isasymdots}\ {\isasymsigma}\isactrlsub n\ {\isasymRightarrow}\ {\isasymlparr}\isactrlvec b\ {\isacharcolon}{\isacharcolon}\ \isactrlvec {\isasymrho}{\isacharcomma}\ \isactrlvec c\ {\isacharcolon}{\isacharcolon}\ \isactrlvec {\isasymsigma}{\isasymrparr}{\isachardoublequote}} \\
|
|
291 |
\end{tabular}
|
|
292 |
\medskip |
|
| 26849 | 293 |
|
| 26852 | 294 |
\noindent Some further operations address the extension aspect of a |
| 26849 | 295 |
derived record scheme specifically: \isa{{\isachardoublequote}t{\isachardot}fields{\isachardoublequote}} produces a
|
296 |
record fragment consisting of exactly the new fields introduced here |
|
297 |
(the result may serve as a more part elsewhere); \isa{{\isachardoublequote}t{\isachardot}extend{\isachardoublequote}}
|
|
298 |
takes a fixed record and adds a given more part; \isa{{\isachardoublequote}t{\isachardot}truncate{\isachardoublequote}} restricts a record scheme to a fixed record.
|
|
299 |
||
| 26852 | 300 |
\medskip |
301 |
\begin{tabular}{lll}
|
|
302 |
\isa{{\isachardoublequote}t{\isachardot}fields{\isachardoublequote}} & \isa{{\isachardoublequote}{\isacharcolon}{\isacharcolon}{\isachardoublequote}} & \isa{{\isachardoublequote}{\isasymsigma}\isactrlsub {\isadigit{1}}\ {\isasymRightarrow}\ {\isasymdots}\ {\isasymsigma}\isactrlsub n\ {\isasymRightarrow}\ {\isasymlparr}\isactrlvec c\ {\isacharcolon}{\isacharcolon}\ \isactrlvec {\isasymsigma}{\isasymrparr}{\isachardoublequote}} \\
|
|
303 |
\isa{{\isachardoublequote}t{\isachardot}extend{\isachardoublequote}} & \isa{{\isachardoublequote}{\isacharcolon}{\isacharcolon}{\isachardoublequote}} & \isa{{\isachardoublequote}{\isasymlparr}\isactrlvec b\ {\isacharcolon}{\isacharcolon}\ \isactrlvec {\isasymrho}{\isacharcomma}\ \isactrlvec c\ {\isacharcolon}{\isacharcolon}\ \isactrlvec {\isasymsigma}{\isasymrparr}\ {\isasymRightarrow}\ {\isasymzeta}\ {\isasymRightarrow}\ {\isasymlparr}\isactrlvec b\ {\isacharcolon}{\isacharcolon}\ \isactrlvec {\isasymrho}{\isacharcomma}\ \isactrlvec c\ {\isacharcolon}{\isacharcolon}\ \isactrlvec {\isasymsigma}{\isacharcomma}\ {\isasymdots}\ {\isacharcolon}{\isacharcolon}\ {\isasymzeta}{\isasymrparr}{\isachardoublequote}} \\
|
|
304 |
\isa{{\isachardoublequote}t{\isachardot}truncate{\isachardoublequote}} & \isa{{\isachardoublequote}{\isacharcolon}{\isacharcolon}{\isachardoublequote}} & \isa{{\isachardoublequote}{\isasymlparr}\isactrlvec b\ {\isacharcolon}{\isacharcolon}\ \isactrlvec {\isasymrho}{\isacharcomma}\ \isactrlvec c\ {\isacharcolon}{\isacharcolon}\ \isactrlvec {\isasymsigma}{\isacharcomma}\ {\isasymdots}\ {\isacharcolon}{\isacharcolon}\ {\isasymzeta}{\isasymrparr}\ {\isasymRightarrow}\ {\isasymlparr}\isactrlvec b\ {\isacharcolon}{\isacharcolon}\ \isactrlvec {\isasymrho}{\isacharcomma}\ \isactrlvec c\ {\isacharcolon}{\isacharcolon}\ \isactrlvec {\isasymsigma}{\isasymrparr}{\isachardoublequote}} \\
|
|
305 |
\end{tabular}
|
|
306 |
\medskip |
|
| 26849 | 307 |
|
308 |
\noindent Note that \isa{{\isachardoublequote}t{\isachardot}make{\isachardoublequote}} and \isa{{\isachardoublequote}t{\isachardot}fields{\isachardoublequote}} coincide
|
|
309 |
for root records.% |
|
310 |
\end{isamarkuptext}%
|
|
311 |
\isamarkuptrue% |
|
312 |
% |
|
313 |
\isamarkupsubsection{Derived rules and proof tools%
|
|
314 |
} |
|
315 |
\isamarkuptrue% |
|
316 |
% |
|
317 |
\begin{isamarkuptext}%
|
|
318 |
The record package proves several results internally, declaring |
|
319 |
these facts to appropriate proof tools. This enables users to |
|
320 |
reason about record structures quite conveniently. Assume that |
|
321 |
\isa{t} is a record type as specified above.
|
|
322 |
||
323 |
\begin{enumerate}
|
|
324 |
||
325 |
\item Standard conversions for selectors or updates applied to |
|
326 |
record constructor terms are made part of the default Simplifier |
|
327 |
context; thus proofs by reduction of basic operations merely require |
|
328 |
the \mbox{\isa{simp}} method without further arguments. These rules
|
|
329 |
are available as \isa{{\isachardoublequote}t{\isachardot}simps{\isachardoublequote}}, too.
|
|
330 |
||
331 |
\item Selectors applied to updated records are automatically reduced |
|
332 |
by an internal simplification procedure, which is also part of the |
|
333 |
standard Simplifier setup. |
|
334 |
||
335 |
\item Inject equations of a form analogous to \isa{{\isachardoublequote}{\isacharparenleft}x{\isacharcomma}\ y{\isacharparenright}\ {\isacharequal}\ {\isacharparenleft}x{\isacharprime}{\isacharcomma}\ y{\isacharprime}{\isacharparenright}\ {\isasymequiv}\ x\ {\isacharequal}\ x{\isacharprime}\ {\isasymand}\ y\ {\isacharequal}\ y{\isacharprime}{\isachardoublequote}} are declared to the Simplifier and Classical
|
|
336 |
Reasoner as \mbox{\isa{iff}} rules. These rules are available as
|
|
337 |
\isa{{\isachardoublequote}t{\isachardot}iffs{\isachardoublequote}}.
|
|
338 |
||
339 |
\item The introduction rule for record equality analogous to \isa{{\isachardoublequote}x\ r\ {\isacharequal}\ x\ r{\isacharprime}\ {\isasymLongrightarrow}\ y\ r\ {\isacharequal}\ y\ r{\isacharprime}\ {\isasymdots}\ {\isasymLongrightarrow}\ r\ {\isacharequal}\ r{\isacharprime}{\isachardoublequote}} is declared to the Simplifier,
|
|
340 |
and as the basic rule context as ``\mbox{\isa{intro}}\isa{{\isachardoublequote}{\isacharquery}{\isachardoublequote}}''.
|
|
341 |
The rule is called \isa{{\isachardoublequote}t{\isachardot}equality{\isachardoublequote}}.
|
|
342 |
||
343 |
\item Representations of arbitrary record expressions as canonical |
|
344 |
constructor terms are provided both in \mbox{\isa{cases}} and \mbox{\isa{induct}} format (cf.\ the generic proof methods of the same name,
|
|
345 |
\secref{sec:cases-induct}). Several variations are available, for
|
|
346 |
fixed records, record schemes, more parts etc. |
|
347 |
||
348 |
The generic proof methods are sufficiently smart to pick the most |
|
349 |
sensible rule according to the type of the indicated record |
|
350 |
expression: users just need to apply something like ``\isa{{\isachardoublequote}{\isacharparenleft}cases\ r{\isacharparenright}{\isachardoublequote}}'' to a certain proof problem.
|
|
351 |
||
352 |
\item The derived record operations \isa{{\isachardoublequote}t{\isachardot}make{\isachardoublequote}}, \isa{{\isachardoublequote}t{\isachardot}fields{\isachardoublequote}}, \isa{{\isachardoublequote}t{\isachardot}extend{\isachardoublequote}}, \isa{{\isachardoublequote}t{\isachardot}truncate{\isachardoublequote}} are \emph{not}
|
|
353 |
treated automatically, but usually need to be expanded by hand, |
|
354 |
using the collective fact \isa{{\isachardoublequote}t{\isachardot}defs{\isachardoublequote}}.
|
|
355 |
||
356 |
\end{enumerate}%
|
|
357 |
\end{isamarkuptext}%
|
|
358 |
\isamarkuptrue% |
|
359 |
% |
|
360 |
\isamarkupsection{Datatypes \label{sec:hol-datatype}%
|
|
361 |
} |
|
362 |
\isamarkuptrue% |
|
363 |
% |
|
364 |
\begin{isamarkuptext}%
|
|
365 |
\begin{matharray}{rcl}
|
|
366 |
\indexdef{HOL}{command}{datatype}\mbox{\isa{\isacommand{datatype}}} & : & \isartrans{theory}{theory} \\
|
|
|
26854
9b4aec46ad78
improved treatment of "_" thanks to underscore.sty;
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parents:
26852
diff
changeset
|
367 |
\indexdef{HOL}{command}{rep\_datatype}\mbox{\isa{\isacommand{rep{\isacharunderscore}datatype}}} & : & \isartrans{theory}{theory} \\
|
| 26849 | 368 |
\end{matharray}
|
369 |
||
370 |
\begin{rail}
|
|
371 |
'datatype' (dtspec + 'and') |
|
372 |
; |
|
373 |
'rep\_datatype' (name *) dtrules |
|
374 |
; |
|
375 |
||
376 |
dtspec: parname? typespec infix? '=' (cons + '|') |
|
377 |
; |
|
378 |
cons: name (type *) mixfix? |
|
379 |
; |
|
380 |
dtrules: 'distinct' thmrefs 'inject' thmrefs 'induction' thmrefs |
|
381 |
\end{rail}
|
|
382 |
||
383 |
\begin{descr}
|
|
384 |
||
385 |
\item [\mbox{\isa{\isacommand{datatype}}}] defines inductive datatypes in
|
|
386 |
HOL. |
|
387 |
||
388 |
\item [\mbox{\isa{\isacommand{rep{\isacharunderscore}datatype}}}] represents existing types as
|
|
389 |
inductive ones, generating the standard infrastructure of derived |
|
390 |
concepts (primitive recursion etc.). |
|
391 |
||
392 |
\end{descr}
|
|
393 |
||
394 |
The induction and exhaustion theorems generated provide case names |
|
395 |
according to the constructors involved, while parameters are named |
|
396 |
after the types (see also \secref{sec:cases-induct}).
|
|
397 |
||
398 |
See \cite{isabelle-HOL} for more details on datatypes, but beware of
|
|
399 |
the old-style theory syntax being used there! Apart from proper |
|
400 |
proof methods for case-analysis and induction, there are also |
|
401 |
emulations of ML tactics \mbox{\isa{case{\isacharunderscore}tac}} and \mbox{\isa{induct{\isacharunderscore}tac}} available, see \secref{sec:hol-induct-tac}; these admit
|
|
402 |
to refer directly to the internal structure of subgoals (including |
|
403 |
internally bound parameters).% |
|
404 |
\end{isamarkuptext}%
|
|
405 |
\isamarkuptrue% |
|
406 |
% |
|
407 |
\isamarkupsection{Recursive functions \label{sec:recursion}%
|
|
408 |
} |
|
409 |
\isamarkuptrue% |
|
410 |
% |
|
411 |
\begin{isamarkuptext}%
|
|
412 |
\begin{matharray}{rcl}
|
|
413 |
\indexdef{HOL}{command}{primrec}\mbox{\isa{\isacommand{primrec}}} & : & \isarkeep{local{\dsh}theory} \\
|
|
414 |
\indexdef{HOL}{command}{fun}\mbox{\isa{\isacommand{fun}}} & : & \isarkeep{local{\dsh}theory} \\
|
|
415 |
\indexdef{HOL}{command}{function}\mbox{\isa{\isacommand{function}}} & : & \isartrans{local{\dsh}theory}{proof(prove)} \\
|
|
416 |
\indexdef{HOL}{command}{termination}\mbox{\isa{\isacommand{termination}}} & : & \isartrans{local{\dsh}theory}{proof(prove)} \\
|
|
417 |
\end{matharray}
|
|
418 |
||
419 |
\railalias{funopts}{function\_opts} %FIXME ??
|
|
420 |
||
421 |
\begin{rail}
|
|
422 |
'primrec' target? fixes 'where' equations |
|
423 |
; |
|
424 |
equations: (thmdecl? prop + '|') |
|
425 |
; |
|
426 |
('fun' | 'function') (funopts)? fixes 'where' clauses
|
|
427 |
; |
|
428 |
clauses: (thmdecl? prop ('(' 'otherwise' ')')? + '|')
|
|
429 |
; |
|
430 |
funopts: '(' (('sequential' | 'in' name | 'domintros' | 'tailrec' |
|
|
431 |
'default' term) + ',') ')' |
|
432 |
; |
|
433 |
'termination' ( term )? |
|
434 |
\end{rail}
|
|
435 |
||
436 |
\begin{descr}
|
|
437 |
||
438 |
\item [\mbox{\isa{\isacommand{primrec}}}] defines primitive recursive
|
|
439 |
functions over datatypes, see also \cite{isabelle-HOL}.
|
|
440 |
||
441 |
\item [\mbox{\isa{\isacommand{function}}}] defines functions by general
|
|
442 |
wellfounded recursion. A detailed description with examples can be |
|
443 |
found in \cite{isabelle-function}. The function is specified by a
|
|
444 |
set of (possibly conditional) recursive equations with arbitrary |
|
445 |
pattern matching. The command generates proof obligations for the |
|
446 |
completeness and the compatibility of patterns. |
|
447 |
||
448 |
The defined function is considered partial, and the resulting |
|
449 |
simplification rules (named \isa{{\isachardoublequote}f{\isachardot}psimps{\isachardoublequote}}) and induction rule
|
|
450 |
(named \isa{{\isachardoublequote}f{\isachardot}pinduct{\isachardoublequote}}) are guarded by a generated domain
|
|
451 |
predicate \isa{{\isachardoublequote}f{\isacharunderscore}dom{\isachardoublequote}}. The \mbox{\isa{\isacommand{termination}}}
|
|
452 |
command can then be used to establish that the function is total. |
|
453 |
||
454 |
\item [\mbox{\isa{\isacommand{fun}}}] is a shorthand notation for
|
|
455 |
``\mbox{\isa{\isacommand{function}}}~\isa{{\isachardoublequote}{\isacharparenleft}sequential{\isacharparenright}{\isachardoublequote}}, followed by
|
|
456 |
automated proof attempts regarding pattern matching and termination. |
|
457 |
See \cite{isabelle-function} for further details.
|
|
458 |
||
459 |
\item [\mbox{\isa{\isacommand{termination}}}~\isa{f}] commences a
|
|
460 |
termination proof for the previously defined function \isa{f}. If
|
|
461 |
this is omitted, the command refers to the most recent function |
|
462 |
definition. After the proof is closed, the recursive equations and |
|
463 |
the induction principle is established. |
|
464 |
||
465 |
\end{descr}
|
|
466 |
||
467 |
%FIXME check |
|
468 |
||
469 |
Recursive definitions introduced by both the \mbox{\isa{\isacommand{primrec}}} and the \mbox{\isa{\isacommand{function}}} command accommodate
|
|
470 |
reasoning by induction (cf.\ \secref{sec:cases-induct}): rule \isa{{\isachardoublequote}c{\isachardot}induct{\isachardoublequote}} (where \isa{c} is the name of the function definition)
|
|
471 |
refers to a specific induction rule, with parameters named according |
|
472 |
to the user-specified equations. Case names of \mbox{\isa{\isacommand{primrec}}} are that of the datatypes involved, while those of
|
|
473 |
\mbox{\isa{\isacommand{function}}} are numbered (starting from 1).
|
|
474 |
||
475 |
The equations provided by these packages may be referred later as |
|
476 |
theorem list \isa{{\isachardoublequote}f{\isachardot}simps{\isachardoublequote}}, where \isa{f} is the (collective)
|
|
477 |
name of the functions defined. Individual equations may be named |
|
478 |
explicitly as well. |
|
479 |
||
480 |
The \mbox{\isa{\isacommand{function}}} command accepts the following
|
|
481 |
options. |
|
482 |
||
483 |
\begin{descr}
|
|
484 |
||
485 |
\item [\isa{sequential}] enables a preprocessor which
|
|
486 |
disambiguates overlapping patterns by making them mutually disjoint. |
|
487 |
Earlier equations take precedence over later ones. This allows to |
|
488 |
give the specification in a format very similar to functional |
|
489 |
programming. Note that the resulting simplification and induction |
|
490 |
rules correspond to the transformed specification, not the one given |
|
491 |
originally. This usually means that each equation given by the user |
|
492 |
may result in several theroems. Also note that this automatic |
|
493 |
transformation only works for ML-style datatype patterns. |
|
494 |
||
495 |
\item [\isa{{\isachardoublequote}{\isasymIN}\ name{\isachardoublequote}}] gives the target for the definition.
|
|
496 |
%FIXME ?!? |
|
497 |
||
498 |
\item [\isa{domintros}] enables the automated generation of
|
|
499 |
introduction rules for the domain predicate. While mostly not |
|
500 |
needed, they can be helpful in some proofs about partial functions. |
|
501 |
||
502 |
\item [\isa{tailrec}] generates the unconstrained recursive
|
|
503 |
equations even without a termination proof, provided that the |
|
504 |
function is tail-recursive. This currently only works |
|
505 |
||
506 |
\item [\isa{{\isachardoublequote}default\ d{\isachardoublequote}}] allows to specify a default value for a
|
|
507 |
(partial) function, which will ensure that \isa{{\isachardoublequote}f\ x\ {\isacharequal}\ d\ x{\isachardoublequote}}
|
|
508 |
whenever \isa{{\isachardoublequote}x\ {\isasymnotin}\ f{\isacharunderscore}dom{\isachardoublequote}}.
|
|
509 |
||
510 |
\end{descr}%
|
|
511 |
\end{isamarkuptext}%
|
|
512 |
\isamarkuptrue% |
|
513 |
% |
|
514 |
\isamarkupsubsection{Proof methods related to recursive definitions%
|
|
515 |
} |
|
516 |
\isamarkuptrue% |
|
517 |
% |
|
518 |
\begin{isamarkuptext}%
|
|
519 |
\begin{matharray}{rcl}
|
|
|
26854
9b4aec46ad78
improved treatment of "_" thanks to underscore.sty;
wenzelm
parents:
26852
diff
changeset
|
520 |
\indexdef{HOL}{method}{pat\_completeness}\mbox{\isa{pat{\isacharunderscore}completeness}} & : & \isarmeth \\
|
| 26849 | 521 |
\indexdef{HOL}{method}{relation}\mbox{\isa{relation}} & : & \isarmeth \\
|
|
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|
522 |
\indexdef{HOL}{method}{lexicographic\_order}\mbox{\isa{lexicographic{\isacharunderscore}order}} & : & \isarmeth \\
|
| 26849 | 523 |
\end{matharray}
|
524 |
||
525 |
\begin{rail}
|
|
526 |
'relation' term |
|
527 |
; |
|
528 |
'lexicographic\_order' (clasimpmod *) |
|
529 |
; |
|
530 |
\end{rail}
|
|
531 |
||
532 |
\begin{descr}
|
|
533 |
||
534 |
\item [\mbox{\isa{pat{\isacharunderscore}completeness}}] is a specialized method to
|
|
535 |
solve goals regarding the completeness of pattern matching, as |
|
536 |
required by the \mbox{\isa{\isacommand{function}}} package (cf.\
|
|
537 |
\cite{isabelle-function}).
|
|
538 |
||
539 |
\item [\mbox{\isa{relation}}~\isa{R}] introduces a termination
|
|
540 |
proof using the relation \isa{R}. The resulting proof state will
|
|
541 |
contain goals expressing that \isa{R} is wellfounded, and that the
|
|
542 |
arguments of recursive calls decrease with respect to \isa{R}.
|
|
543 |
Usually, this method is used as the initial proof step of manual |
|
544 |
termination proofs. |
|
545 |
||
546 |
\item [\mbox{\isa{lexicographic{\isacharunderscore}order}}] attempts a fully
|
|
547 |
automated termination proof by searching for a lexicographic |
|
548 |
combination of size measures on the arguments of the function. The |
|
549 |
method accepts the same arguments as the \mbox{\isa{auto}} method,
|
|
550 |
which it uses internally to prove local descents. The same context |
|
551 |
modifiers as for \mbox{\isa{auto}} are accepted, see
|
|
552 |
\secref{sec:clasimp}.
|
|
553 |
||
554 |
In case of failure, extensive information is printed, which can help |
|
555 |
to analyse the situation (cf.\ \cite{isabelle-function}).
|
|
556 |
||
557 |
\end{descr}%
|
|
558 |
\end{isamarkuptext}%
|
|
559 |
\isamarkuptrue% |
|
560 |
% |
|
561 |
\isamarkupsubsection{Old-style recursive function definitions (TFL)%
|
|
562 |
} |
|
563 |
\isamarkuptrue% |
|
564 |
% |
|
565 |
\begin{isamarkuptext}%
|
|
566 |
The old TFL commands \mbox{\isa{\isacommand{recdef}}} and \mbox{\isa{\isacommand{recdef{\isacharunderscore}tc}}} for defining recursive are mostly obsolete; \mbox{\isa{\isacommand{function}}} or \mbox{\isa{\isacommand{fun}}} should be used instead.
|
|
567 |
||
568 |
\begin{matharray}{rcl}
|
|
569 |
\indexdef{HOL}{command}{recdef}\mbox{\isa{\isacommand{recdef}}} & : & \isartrans{theory}{theory} \\
|
|
|
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|
570 |
\indexdef{HOL}{command}{recdef\_tc}\mbox{\isa{\isacommand{recdef{\isacharunderscore}tc}}}\isa{{\isachardoublequote}\isactrlsup {\isacharasterisk}{\isachardoublequote}} & : & \isartrans{theory}{proof(prove)} \\
|
| 26849 | 571 |
\end{matharray}
|
572 |
||
573 |
\begin{rail}
|
|
574 |
'recdef' ('(' 'permissive' ')')? \\ name term (prop +) hints?
|
|
575 |
; |
|
576 |
recdeftc thmdecl? tc |
|
577 |
; |
|
578 |
hints: '(' 'hints' (recdefmod *) ')'
|
|
579 |
; |
|
580 |
recdefmod: (('recdef\_simp' | 'recdef\_cong' | 'recdef\_wf') (() | 'add' | 'del') ':' thmrefs) | clasimpmod
|
|
581 |
; |
|
582 |
tc: nameref ('(' nat ')')?
|
|
583 |
; |
|
584 |
\end{rail}
|
|
585 |
||
586 |
\begin{descr}
|
|
587 |
||
588 |
\item [\mbox{\isa{\isacommand{recdef}}}] defines general well-founded
|
|
589 |
recursive functions (using the TFL package), see also |
|
590 |
\cite{isabelle-HOL}. The ``\isa{{\isachardoublequote}{\isacharparenleft}permissive{\isacharparenright}{\isachardoublequote}}'' option tells
|
|
591 |
TFL to recover from failed proof attempts, returning unfinished |
|
592 |
results. The \isa{recdef{\isacharunderscore}simp}, \isa{recdef{\isacharunderscore}cong}, and \isa{recdef{\isacharunderscore}wf} hints refer to auxiliary rules to be used in the internal
|
|
593 |
automated proof process of TFL. Additional \mbox{\isa{clasimpmod}}
|
|
594 |
declarations (cf.\ \secref{sec:clasimp}) may be given to tune the
|
|
595 |
context of the Simplifier (cf.\ \secref{sec:simplifier}) and
|
|
596 |
Classical reasoner (cf.\ \secref{sec:classical}).
|
|
597 |
||
598 |
\item [\mbox{\isa{\isacommand{recdef{\isacharunderscore}tc}}}~\isa{{\isachardoublequote}c\ {\isacharparenleft}i{\isacharparenright}{\isachardoublequote}}] recommences the
|
|
599 |
proof for leftover termination condition number \isa{i} (default
|
|
600 |
1) as generated by a \mbox{\isa{\isacommand{recdef}}} definition of
|
|
601 |
constant \isa{c}.
|
|
602 |
||
603 |
Note that in most cases, \mbox{\isa{\isacommand{recdef}}} is able to finish
|
|
604 |
its internal proofs without manual intervention. |
|
605 |
||
606 |
\end{descr}
|
|
607 |
||
608 |
\medskip Hints for \mbox{\isa{\isacommand{recdef}}} may be also declared
|
|
609 |
globally, using the following attributes. |
|
610 |
||
611 |
\begin{matharray}{rcl}
|
|
|
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|
612 |
\indexdef{HOL}{attribute}{recdef\_simp}\mbox{\isa{recdef{\isacharunderscore}simp}} & : & \isaratt \\
|
|
9b4aec46ad78
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parents:
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changeset
|
613 |
\indexdef{HOL}{attribute}{recdef\_cong}\mbox{\isa{recdef{\isacharunderscore}cong}} & : & \isaratt \\
|
|
9b4aec46ad78
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changeset
|
614 |
\indexdef{HOL}{attribute}{recdef\_wf}\mbox{\isa{recdef{\isacharunderscore}wf}} & : & \isaratt \\
|
| 26849 | 615 |
\end{matharray}
|
616 |
||
617 |
\begin{rail}
|
|
618 |
('recdef\_simp' | 'recdef\_cong' | 'recdef\_wf') (() | 'add' | 'del')
|
|
619 |
; |
|
620 |
\end{rail}%
|
|
621 |
\end{isamarkuptext}%
|
|
622 |
\isamarkuptrue% |
|
623 |
% |
|
624 |
\isamarkupsection{Definition by specification \label{sec:hol-specification}%
|
|
625 |
} |
|
626 |
\isamarkuptrue% |
|
627 |
% |
|
628 |
\begin{isamarkuptext}%
|
|
629 |
\begin{matharray}{rcl}
|
|
630 |
\indexdef{HOL}{command}{specification}\mbox{\isa{\isacommand{specification}}} & : & \isartrans{theory}{proof(prove)} \\
|
|
|
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parents:
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changeset
|
631 |
\indexdef{HOL}{command}{ax\_specification}\mbox{\isa{\isacommand{ax{\isacharunderscore}specification}}} & : & \isartrans{theory}{proof(prove)} \\
|
| 26849 | 632 |
\end{matharray}
|
633 |
||
634 |
\begin{rail}
|
|
635 |
('specification' | 'ax\_specification') '(' (decl +) ')' \\ (thmdecl? prop +)
|
|
636 |
; |
|
637 |
decl: ((name ':')? term '(' 'overloaded' ')'?)
|
|
638 |
\end{rail}
|
|
639 |
||
640 |
\begin{descr}
|
|
641 |
||
642 |
\item [\mbox{\isa{\isacommand{specification}}}~\isa{{\isachardoublequote}decls\ {\isasymphi}{\isachardoublequote}}] sets up a
|
|
643 |
goal stating the existence of terms with the properties specified to |
|
644 |
hold for the constants given in \isa{decls}. After finishing the
|
|
645 |
proof, the theory will be augmented with definitions for the given |
|
646 |
constants, as well as with theorems stating the properties for these |
|
647 |
constants. |
|
648 |
||
649 |
\item [\mbox{\isa{\isacommand{ax{\isacharunderscore}specification}}}~\isa{{\isachardoublequote}decls\ {\isasymphi}{\isachardoublequote}}] sets
|
|
650 |
up a goal stating the existence of terms with the properties |
|
651 |
specified to hold for the constants given in \isa{decls}. After
|
|
652 |
finishing the proof, the theory will be augmented with axioms |
|
653 |
expressing the properties given in the first place. |
|
654 |
||
655 |
\item [\isa{decl}] declares a constant to be defined by the
|
|
656 |
specification given. The definition for the constant \isa{c} is
|
|
657 |
bound to the name \isa{c{\isacharunderscore}def} unless a theorem name is given in
|
|
658 |
the declaration. Overloaded constants should be declared as such. |
|
659 |
||
660 |
\end{descr}
|
|
661 |
||
662 |
Whether to use \mbox{\isa{\isacommand{specification}}} or \mbox{\isa{\isacommand{ax{\isacharunderscore}specification}}} is to some extent a matter of style. \mbox{\isa{\isacommand{specification}}} introduces no new axioms, and so by
|
|
663 |
construction cannot introduce inconsistencies, whereas \mbox{\isa{\isacommand{ax{\isacharunderscore}specification}}} does introduce axioms, but only after the
|
|
664 |
user has explicitly proven it to be safe. A practical issue must be |
|
665 |
considered, though: After introducing two constants with the same |
|
666 |
properties using \mbox{\isa{\isacommand{specification}}}, one can prove
|
|
667 |
that the two constants are, in fact, equal. If this might be a |
|
668 |
problem, one should use \mbox{\isa{\isacommand{ax{\isacharunderscore}specification}}}.%
|
|
669 |
\end{isamarkuptext}%
|
|
670 |
\isamarkuptrue% |
|
671 |
% |
|
672 |
\isamarkupsection{Inductive and coinductive definitions \label{sec:hol-inductive}%
|
|
673 |
} |
|
674 |
\isamarkuptrue% |
|
675 |
% |
|
676 |
\begin{isamarkuptext}%
|
|
677 |
An \textbf{inductive definition} specifies the least predicate (or
|
|
678 |
set) \isa{R} closed under given rules: applying a rule to elements
|
|
679 |
of \isa{R} yields a result within \isa{R}. For example, a
|
|
680 |
structural operational semantics is an inductive definition of an |
|
681 |
evaluation relation. |
|
682 |
||
683 |
Dually, a \textbf{coinductive definition} specifies the greatest
|
|
684 |
predicate~/ set \isa{R} that is consistent with given rules: every
|
|
685 |
element of \isa{R} can be seen as arising by applying a rule to
|
|
686 |
elements of \isa{R}. An important example is using bisimulation
|
|
687 |
relations to formalise equivalence of processes and infinite data |
|
688 |
structures. |
|
689 |
||
690 |
\medskip The HOL package is related to the ZF one, which is |
|
691 |
described in a separate paper,\footnote{It appeared in CADE
|
|
692 |
\cite{paulson-CADE}; a longer version is distributed with Isabelle.}
|
|
693 |
which you should refer to in case of difficulties. The package is |
|
694 |
simpler than that of ZF thanks to implicit type-checking in HOL. |
|
695 |
The types of the (co)inductive predicates (or sets) determine the |
|
696 |
domain of the fixedpoint definition, and the package does not have |
|
697 |
to use inference rules for type-checking. |
|
698 |
||
699 |
\begin{matharray}{rcl}
|
|
700 |
\indexdef{HOL}{command}{inductive}\mbox{\isa{\isacommand{inductive}}} & : & \isarkeep{local{\dsh}theory} \\
|
|
|
26854
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parents:
26852
diff
changeset
|
701 |
\indexdef{HOL}{command}{inductive\_set}\mbox{\isa{\isacommand{inductive{\isacharunderscore}set}}} & : & \isarkeep{local{\dsh}theory} \\
|
| 26849 | 702 |
\indexdef{HOL}{command}{coinductive}\mbox{\isa{\isacommand{coinductive}}} & : & \isarkeep{local{\dsh}theory} \\
|
|
26854
9b4aec46ad78
improved treatment of "_" thanks to underscore.sty;
wenzelm
parents:
26852
diff
changeset
|
703 |
\indexdef{HOL}{command}{coinductive\_set}\mbox{\isa{\isacommand{coinductive{\isacharunderscore}set}}} & : & \isarkeep{local{\dsh}theory} \\
|
| 26849 | 704 |
\indexdef{HOL}{attribute}{mono}\mbox{\isa{mono}} & : & \isaratt \\
|
705 |
\end{matharray}
|
|
706 |
||
707 |
\begin{rail}
|
|
708 |
('inductive' | 'inductive\_set' | 'coinductive' | 'coinductive\_set') target? fixes ('for' fixes)? \\
|
|
709 |
('where' clauses)? ('monos' thmrefs)?
|
|
710 |
; |
|
711 |
clauses: (thmdecl? prop + '|') |
|
712 |
; |
|
713 |
'mono' (() | 'add' | 'del') |
|
714 |
; |
|
715 |
\end{rail}
|
|
716 |
||
717 |
\begin{descr}
|
|
718 |
||
719 |
\item [\mbox{\isa{\isacommand{inductive}}} and \mbox{\isa{\isacommand{coinductive}}}] define (co)inductive predicates from the
|
|
720 |
introduction rules given in the \mbox{\isa{\isakeyword{where}}} part. The
|
|
721 |
optional \mbox{\isa{\isakeyword{for}}} part contains a list of parameters of the
|
|
722 |
(co)inductive predicates that remain fixed throughout the |
|
723 |
definition. The optional \mbox{\isa{\isakeyword{monos}}} section contains
|
|
724 |
\emph{monotonicity theorems}, which are required for each operator
|
|
725 |
applied to a recursive set in the introduction rules. There |
|
726 |
\emph{must} be a theorem of the form \isa{{\isachardoublequote}A\ {\isasymle}\ B\ {\isasymLongrightarrow}\ M\ A\ {\isasymle}\ M\ B{\isachardoublequote}},
|
|
727 |
for each premise \isa{{\isachardoublequote}M\ R\isactrlsub i\ t{\isachardoublequote}} in an introduction rule!
|
|
728 |
||
729 |
\item [\mbox{\isa{\isacommand{inductive{\isacharunderscore}set}}} and \mbox{\isa{\isacommand{coinductive{\isacharunderscore}set}}}] are wrappers for to the previous commands,
|
|
730 |
allowing the definition of (co)inductive sets. |
|
731 |
||
732 |
\item [\mbox{\isa{mono}}] declares monotonicity rules. These
|
|
733 |
rule are involved in the automated monotonicity proof of \mbox{\isa{\isacommand{inductive}}}.
|
|
734 |
||
735 |
\end{descr}%
|
|
736 |
\end{isamarkuptext}%
|
|
737 |
\isamarkuptrue% |
|
738 |
% |
|
739 |
\isamarkupsubsection{Derived rules%
|
|
740 |
} |
|
741 |
\isamarkuptrue% |
|
742 |
% |
|
743 |
\begin{isamarkuptext}%
|
|
744 |
Each (co)inductive definition \isa{R} adds definitions to the
|
|
745 |
theory and also proves some theorems: |
|
746 |
||
747 |
\begin{description}
|
|
748 |
||
749 |
\item [\isa{R{\isachardot}intros}] is the list of introduction rules as proven
|
|
750 |
theorems, for the recursive predicates (or sets). The rules are |
|
751 |
also available individually, using the names given them in the |
|
752 |
theory file; |
|
753 |
||
754 |
\item [\isa{R{\isachardot}cases}] is the case analysis (or elimination) rule;
|
|
755 |
||
756 |
\item [\isa{R{\isachardot}induct} or \isa{R{\isachardot}coinduct}] is the (co)induction
|
|
757 |
rule. |
|
758 |
||
759 |
\end{description}
|
|
760 |
||
761 |
When several predicates \isa{{\isachardoublequote}R\isactrlsub {\isadigit{1}}{\isacharcomma}\ {\isasymdots}{\isacharcomma}\ R\isactrlsub n{\isachardoublequote}} are
|
|
762 |
defined simultaneously, the list of introduction rules is called |
|
763 |
\isa{{\isachardoublequote}R\isactrlsub {\isadigit{1}}{\isacharunderscore}{\isasymdots}{\isacharunderscore}R\isactrlsub n{\isachardot}intros{\isachardoublequote}}, the case analysis rules are
|
|
764 |
called \isa{{\isachardoublequote}R\isactrlsub {\isadigit{1}}{\isachardot}cases{\isacharcomma}\ {\isasymdots}{\isacharcomma}\ R\isactrlsub n{\isachardot}cases{\isachardoublequote}}, and the list
|
|
765 |
of mutual induction rules is called \isa{{\isachardoublequote}R\isactrlsub {\isadigit{1}}{\isacharunderscore}{\isasymdots}{\isacharunderscore}R\isactrlsub n{\isachardot}inducts{\isachardoublequote}}.%
|
|
766 |
\end{isamarkuptext}%
|
|
767 |
\isamarkuptrue% |
|
768 |
% |
|
769 |
\isamarkupsubsection{Monotonicity theorems%
|
|
770 |
} |
|
771 |
\isamarkuptrue% |
|
772 |
% |
|
773 |
\begin{isamarkuptext}%
|
|
774 |
Each theory contains a default set of theorems that are used in |
|
775 |
monotonicity proofs. New rules can be added to this set via the |
|
776 |
\mbox{\isa{mono}} attribute. The HOL theory \isa{Inductive}
|
|
777 |
shows how this is done. In general, the following monotonicity |
|
778 |
theorems may be added: |
|
779 |
||
780 |
\begin{itemize}
|
|
781 |
||
782 |
\item Theorems of the form \isa{{\isachardoublequote}A\ {\isasymle}\ B\ {\isasymLongrightarrow}\ M\ A\ {\isasymle}\ M\ B{\isachardoublequote}}, for proving
|
|
783 |
monotonicity of inductive definitions whose introduction rules have |
|
784 |
premises involving terms such as \isa{{\isachardoublequote}M\ R\isactrlsub i\ t{\isachardoublequote}}.
|
|
785 |
||
786 |
\item Monotonicity theorems for logical operators, which are of the |
|
787 |
general form \isa{{\isachardoublequote}{\isacharparenleft}{\isasymdots}\ {\isasymlongrightarrow}\ {\isasymdots}{\isacharparenright}\ {\isasymLongrightarrow}\ {\isasymdots}\ {\isacharparenleft}{\isasymdots}\ {\isasymlongrightarrow}\ {\isasymdots}{\isacharparenright}\ {\isasymLongrightarrow}\ {\isasymdots}\ {\isasymlongrightarrow}\ {\isasymdots}{\isachardoublequote}}. For example, in
|
|
788 |
the case of the operator \isa{{\isachardoublequote}{\isasymor}{\isachardoublequote}}, the corresponding theorem is
|
|
789 |
\[ |
|
790 |
\infer{\isa{{\isachardoublequote}P\isactrlsub {\isadigit{1}}\ {\isasymor}\ P\isactrlsub {\isadigit{2}}\ {\isasymlongrightarrow}\ Q\isactrlsub {\isadigit{1}}\ {\isasymor}\ Q\isactrlsub {\isadigit{2}}{\isachardoublequote}}}{\isa{{\isachardoublequote}P\isactrlsub {\isadigit{1}}\ {\isasymlongrightarrow}\ Q\isactrlsub {\isadigit{1}}{\isachardoublequote}} & \isa{{\isachardoublequote}P\isactrlsub {\isadigit{2}}\ {\isasymlongrightarrow}\ Q\isactrlsub {\isadigit{2}}{\isachardoublequote}}}
|
|
791 |
\] |
|
792 |
||
793 |
\item De Morgan style equations for reasoning about the ``polarity'' |
|
794 |
of expressions, e.g. |
|
795 |
\[ |
|
796 |
\isa{{\isachardoublequote}{\isasymnot}\ {\isasymnot}\ P\ {\isasymlongleftrightarrow}\ P{\isachardoublequote}} \qquad\qquad
|
|
797 |
\isa{{\isachardoublequote}{\isasymnot}\ {\isacharparenleft}P\ {\isasymand}\ Q{\isacharparenright}\ {\isasymlongleftrightarrow}\ {\isasymnot}\ P\ {\isasymor}\ {\isasymnot}\ Q{\isachardoublequote}}
|
|
798 |
\] |
|
799 |
||
800 |
\item Equations for reducing complex operators to more primitive |
|
801 |
ones whose monotonicity can easily be proved, e.g. |
|
802 |
\[ |
|
803 |
\isa{{\isachardoublequote}{\isacharparenleft}P\ {\isasymlongrightarrow}\ Q{\isacharparenright}\ {\isasymlongleftrightarrow}\ {\isasymnot}\ P\ {\isasymor}\ Q{\isachardoublequote}} \qquad\qquad
|
|
804 |
\isa{{\isachardoublequote}Ball\ A\ P\ {\isasymequiv}\ {\isasymforall}x{\isachardot}\ x\ {\isasymin}\ A\ {\isasymlongrightarrow}\ P\ x{\isachardoublequote}}
|
|
805 |
\] |
|
806 |
||
807 |
\end{itemize}
|
|
808 |
||
809 |
%FIXME: Example of an inductive definition% |
|
810 |
\end{isamarkuptext}%
|
|
811 |
\isamarkuptrue% |
|
812 |
% |
|
813 |
\isamarkupsection{Arithmetic proof support%
|
|
814 |
} |
|
815 |
\isamarkuptrue% |
|
816 |
% |
|
817 |
\begin{isamarkuptext}%
|
|
818 |
\begin{matharray}{rcl}
|
|
819 |
\indexdef{HOL}{method}{arith}\mbox{\isa{arith}} & : & \isarmeth \\
|
|
|
26854
9b4aec46ad78
improved treatment of "_" thanks to underscore.sty;
wenzelm
parents:
26852
diff
changeset
|
820 |
\indexdef{HOL}{method}{arith\_split}\mbox{\isa{arith{\isacharunderscore}split}} & : & \isaratt \\
|
| 26849 | 821 |
\end{matharray}
|
822 |
||
823 |
The \mbox{\isa{arith}} method decides linear arithmetic problems
|
|
824 |
(on types \isa{nat}, \isa{int}, \isa{real}). Any current
|
|
825 |
facts are inserted into the goal before running the procedure. |
|
826 |
||
827 |
The \mbox{\isa{arith{\isacharunderscore}split}} attribute declares case split rules
|
|
828 |
to be expanded before the arithmetic procedure is invoked. |
|
829 |
||
830 |
Note that a simpler (but faster) version of arithmetic reasoning is |
|
831 |
already performed by the Simplifier.% |
|
832 |
\end{isamarkuptext}%
|
|
833 |
\isamarkuptrue% |
|
834 |
% |
|
835 |
\isamarkupsection{Cases and induction: emulating tactic scripts \label{sec:hol-induct-tac}%
|
|
836 |
} |
|
837 |
\isamarkuptrue% |
|
838 |
% |
|
839 |
\begin{isamarkuptext}%
|
|
840 |
The following important tactical tools of Isabelle/HOL have been |
|
841 |
ported to Isar. These should be never used in proper proof texts! |
|
842 |
||
843 |
\begin{matharray}{rcl}
|
|
|
26854
9b4aec46ad78
improved treatment of "_" thanks to underscore.sty;
wenzelm
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26852
diff
changeset
|
844 |
\indexdef{HOL}{method}{case\_tac}\mbox{\isa{case{\isacharunderscore}tac}}\isa{{\isachardoublequote}\isactrlsup {\isacharasterisk}{\isachardoublequote}} & : & \isarmeth \\
|
|
9b4aec46ad78
improved treatment of "_" thanks to underscore.sty;
wenzelm
parents:
26852
diff
changeset
|
845 |
\indexdef{HOL}{method}{induct\_tac}\mbox{\isa{induct{\isacharunderscore}tac}}\isa{{\isachardoublequote}\isactrlsup {\isacharasterisk}{\isachardoublequote}} & : & \isarmeth \\
|
|
9b4aec46ad78
improved treatment of "_" thanks to underscore.sty;
wenzelm
parents:
26852
diff
changeset
|
846 |
\indexdef{HOL}{method}{ind\_cases}\mbox{\isa{ind{\isacharunderscore}cases}}\isa{{\isachardoublequote}\isactrlsup {\isacharasterisk}{\isachardoublequote}} & : & \isarmeth \\
|
|
9b4aec46ad78
improved treatment of "_" thanks to underscore.sty;
wenzelm
parents:
26852
diff
changeset
|
847 |
\indexdef{HOL}{command}{inductive\_cases}\mbox{\isa{\isacommand{inductive{\isacharunderscore}cases}}} & : & \isartrans{theory}{theory} \\
|
| 26849 | 848 |
\end{matharray}
|
849 |
||
850 |
\begin{rail}
|
|
851 |
'case\_tac' goalspec? term rule? |
|
852 |
; |
|
853 |
'induct\_tac' goalspec? (insts * 'and') rule? |
|
854 |
; |
|
855 |
'ind\_cases' (prop +) ('for' (name +)) ?
|
|
856 |
; |
|
857 |
'inductive\_cases' (thmdecl? (prop +) + 'and') |
|
858 |
; |
|
859 |
||
860 |
rule: ('rule' ':' thmref)
|
|
861 |
; |
|
862 |
\end{rail}
|
|
863 |
||
864 |
\begin{descr}
|
|
865 |
||
866 |
\item [\mbox{\isa{case{\isacharunderscore}tac}} and \mbox{\isa{induct{\isacharunderscore}tac}}]
|
|
867 |
admit to reason about inductive datatypes only (unless an |
|
868 |
alternative rule is given explicitly). Furthermore, \mbox{\isa{case{\isacharunderscore}tac}} does a classical case split on booleans; \mbox{\isa{induct{\isacharunderscore}tac}} allows only variables to be given as instantiation.
|
|
869 |
These tactic emulations feature both goal addressing and dynamic |
|
870 |
instantiation. Note that named rule cases are \emph{not} provided
|
|
871 |
as would be by the proper \mbox{\isa{induct}} and \mbox{\isa{cases}} proof
|
|
872 |
methods (see \secref{sec:cases-induct}).
|
|
873 |
||
874 |
\item [\mbox{\isa{ind{\isacharunderscore}cases}} and \mbox{\isa{\isacommand{inductive{\isacharunderscore}cases}}}] provide an interface to the internal
|
|
875 |
\texttt{mk_cases} operation. Rules are simplified in an
|
|
876 |
unrestricted forward manner. |
|
877 |
||
878 |
While \mbox{\isa{ind{\isacharunderscore}cases}} is a proof method to apply the
|
|
879 |
result immediately as elimination rules, \mbox{\isa{\isacommand{inductive{\isacharunderscore}cases}}} provides case split theorems at the theory level
|
|
880 |
for later use. The \mbox{\isa{\isakeyword{for}}} argument of the \mbox{\isa{ind{\isacharunderscore}cases}} method allows to specify a list of variables that should
|
|
881 |
be generalized before applying the resulting rule. |
|
882 |
||
883 |
\end{descr}%
|
|
884 |
\end{isamarkuptext}%
|
|
885 |
\isamarkuptrue% |
|
886 |
% |
|
887 |
\isamarkupsection{Executable code%
|
|
888 |
} |
|
889 |
\isamarkuptrue% |
|
890 |
% |
|
891 |
\begin{isamarkuptext}%
|
|
892 |
Isabelle/Pure provides two generic frameworks to support code |
|
893 |
generation from executable specifications. Isabelle/HOL |
|
894 |
instantiates these mechanisms in a way that is amenable to end-user |
|
895 |
applications. |
|
896 |
||
897 |
One framework generates code from both functional and relational |
|
898 |
programs to SML. See \cite{isabelle-HOL} for further information
|
|
899 |
(this actually covers the new-style theory format as well). |
|
900 |
||
901 |
\begin{matharray}{rcl}
|
|
902 |
\indexdef{HOL}{command}{value}\mbox{\isa{\isacommand{value}}}\isa{{\isachardoublequote}\isactrlsup {\isacharasterisk}{\isachardoublequote}} & : & \isarkeep{theory~|~proof} \\
|
|
|
26854
9b4aec46ad78
improved treatment of "_" thanks to underscore.sty;
wenzelm
parents:
26852
diff
changeset
|
903 |
\indexdef{HOL}{command}{code\_module}\mbox{\isa{\isacommand{code{\isacharunderscore}module}}} & : & \isartrans{theory}{theory} \\
|
|
9b4aec46ad78
improved treatment of "_" thanks to underscore.sty;
wenzelm
parents:
26852
diff
changeset
|
904 |
\indexdef{HOL}{command}{code\_library}\mbox{\isa{\isacommand{code{\isacharunderscore}library}}} & : & \isartrans{theory}{theory} \\
|
|
9b4aec46ad78
improved treatment of "_" thanks to underscore.sty;
wenzelm
parents:
26852
diff
changeset
|
905 |
\indexdef{HOL}{command}{consts\_code}\mbox{\isa{\isacommand{consts{\isacharunderscore}code}}} & : & \isartrans{theory}{theory} \\
|
|
9b4aec46ad78
improved treatment of "_" thanks to underscore.sty;
wenzelm
parents:
26852
diff
changeset
|
906 |
\indexdef{HOL}{command}{types\_code}\mbox{\isa{\isacommand{types{\isacharunderscore}code}}} & : & \isartrans{theory}{theory} \\
|
| 26849 | 907 |
\indexdef{HOL}{attribute}{code}\mbox{\isa{code}} & : & \isaratt \\
|
908 |
\end{matharray}
|
|
909 |
||
910 |
\begin{rail}
|
|
911 |
'value' term |
|
912 |
; |
|
913 |
||
914 |
( 'code\_module' | 'code\_library' ) modespec ? name ? \\ |
|
915 |
( 'file' name ) ? ( 'imports' ( name + ) ) ? \\ |
|
916 |
'contains' ( ( name '=' term ) + | term + ) |
|
917 |
; |
|
918 |
||
919 |
modespec: '(' ( name * ) ')'
|
|
920 |
; |
|
921 |
||
922 |
'consts\_code' (codespec +) |
|
923 |
; |
|
924 |
||
925 |
codespec: const template attachment ? |
|
926 |
; |
|
927 |
||
928 |
'types\_code' (tycodespec +) |
|
929 |
; |
|
930 |
||
931 |
tycodespec: name template attachment ? |
|
932 |
; |
|
933 |
||
934 |
const: term |
|
935 |
; |
|
936 |
||
937 |
template: '(' string ')'
|
|
938 |
; |
|
939 |
||
940 |
attachment: 'attach' modespec ? verblbrace text verbrbrace |
|
941 |
; |
|
942 |
||
943 |
'code' (name)? |
|
944 |
; |
|
945 |
\end{rail}
|
|
946 |
||
947 |
\begin{descr}
|
|
948 |
||
949 |
\item [\mbox{\isa{\isacommand{value}}}~\isa{t}] evaluates and prints a
|
|
950 |
term using the code generator. |
|
951 |
||
952 |
\end{descr}
|
|
953 |
||
954 |
\medskip The other framework generates code from functional programs |
|
955 |
(including overloading using type classes) to SML \cite{SML}, OCaml
|
|
956 |
\cite{OCaml} and Haskell \cite{haskell-revised-report}.
|
|
957 |
Conceptually, code generation is split up in three steps: |
|
958 |
\emph{selection} of code theorems, \emph{translation} into an
|
|
959 |
abstract executable view and \emph{serialization} to a specific
|
|
960 |
\emph{target language}. See \cite{isabelle-codegen} for an
|
|
961 |
introduction on how to use it. |
|
962 |
||
963 |
\begin{matharray}{rcl}
|
|
|
26854
9b4aec46ad78
improved treatment of "_" thanks to underscore.sty;
wenzelm
parents:
26852
diff
changeset
|
964 |
\indexdef{HOL}{command}{export\_code}\mbox{\isa{\isacommand{export{\isacharunderscore}code}}}\isa{{\isachardoublequote}\isactrlsup {\isacharasterisk}{\isachardoublequote}} & : & \isarkeep{theory~|~proof} \\
|
|
9b4aec46ad78
improved treatment of "_" thanks to underscore.sty;
wenzelm
parents:
26852
diff
changeset
|
965 |
\indexdef{HOL}{command}{code\_thms}\mbox{\isa{\isacommand{code{\isacharunderscore}thms}}}\isa{{\isachardoublequote}\isactrlsup {\isacharasterisk}{\isachardoublequote}} & : & \isarkeep{theory~|~proof} \\
|
|
9b4aec46ad78
improved treatment of "_" thanks to underscore.sty;
wenzelm
parents:
26852
diff
changeset
|
966 |
\indexdef{HOL}{command}{code\_deps}\mbox{\isa{\isacommand{code{\isacharunderscore}deps}}}\isa{{\isachardoublequote}\isactrlsup {\isacharasterisk}{\isachardoublequote}} & : & \isarkeep{theory~|~proof} \\
|
|
9b4aec46ad78
improved treatment of "_" thanks to underscore.sty;
wenzelm
parents:
26852
diff
changeset
|
967 |
\indexdef{HOL}{command}{code\_datatype}\mbox{\isa{\isacommand{code{\isacharunderscore}datatype}}} & : & \isartrans{theory}{theory} \\
|
|
9b4aec46ad78
improved treatment of "_" thanks to underscore.sty;
wenzelm
parents:
26852
diff
changeset
|
968 |
\indexdef{HOL}{command}{code\_const}\mbox{\isa{\isacommand{code{\isacharunderscore}const}}} & : & \isartrans{theory}{theory} \\
|
|
9b4aec46ad78
improved treatment of "_" thanks to underscore.sty;
wenzelm
parents:
26852
diff
changeset
|
969 |
\indexdef{HOL}{command}{code\_type}\mbox{\isa{\isacommand{code{\isacharunderscore}type}}} & : & \isartrans{theory}{theory} \\
|
|
9b4aec46ad78
improved treatment of "_" thanks to underscore.sty;
wenzelm
parents:
26852
diff
changeset
|
970 |
\indexdef{HOL}{command}{code\_class}\mbox{\isa{\isacommand{code{\isacharunderscore}class}}} & : & \isartrans{theory}{theory} \\
|
|
9b4aec46ad78
improved treatment of "_" thanks to underscore.sty;
wenzelm
parents:
26852
diff
changeset
|
971 |
\indexdef{HOL}{command}{code\_instance}\mbox{\isa{\isacommand{code{\isacharunderscore}instance}}} & : & \isartrans{theory}{theory} \\
|
|
9b4aec46ad78
improved treatment of "_" thanks to underscore.sty;
wenzelm
parents:
26852
diff
changeset
|
972 |
\indexdef{HOL}{command}{code\_monad}\mbox{\isa{\isacommand{code{\isacharunderscore}monad}}} & : & \isartrans{theory}{theory} \\
|
|
9b4aec46ad78
improved treatment of "_" thanks to underscore.sty;
wenzelm
parents:
26852
diff
changeset
|
973 |
\indexdef{HOL}{command}{code\_reserved}\mbox{\isa{\isacommand{code{\isacharunderscore}reserved}}} & : & \isartrans{theory}{theory} \\
|
|
9b4aec46ad78
improved treatment of "_" thanks to underscore.sty;
wenzelm
parents:
26852
diff
changeset
|
974 |
\indexdef{HOL}{command}{code\_include}\mbox{\isa{\isacommand{code{\isacharunderscore}include}}} & : & \isartrans{theory}{theory} \\
|
|
9b4aec46ad78
improved treatment of "_" thanks to underscore.sty;
wenzelm
parents:
26852
diff
changeset
|
975 |
\indexdef{HOL}{command}{code\_modulename}\mbox{\isa{\isacommand{code{\isacharunderscore}modulename}}} & : & \isartrans{theory}{theory} \\
|
|
9b4aec46ad78
improved treatment of "_" thanks to underscore.sty;
wenzelm
parents:
26852
diff
changeset
|
976 |
\indexdef{HOL}{command}{code\_exception}\mbox{\isa{\isacommand{code{\isacharunderscore}exception}}} & : & \isartrans{theory}{theory} \\
|
|
9b4aec46ad78
improved treatment of "_" thanks to underscore.sty;
wenzelm
parents:
26852
diff
changeset
|
977 |
\indexdef{HOL}{command}{print\_codesetup}\mbox{\isa{\isacommand{print{\isacharunderscore}codesetup}}}\isa{{\isachardoublequote}\isactrlsup {\isacharasterisk}{\isachardoublequote}} & : & \isarkeep{theory~|~proof} \\
|
| 26849 | 978 |
\indexdef{HOL}{attribute}{code}\mbox{\isa{code}} & : & \isaratt \\
|
979 |
\end{matharray}
|
|
980 |
||
981 |
\begin{rail}
|
|
982 |
'export\_code' ( constexpr + ) ? \\ |
|
983 |
( ( 'in' target ( 'module\_name' string ) ? \\ |
|
984 |
( 'file' ( string | '-' ) ) ? ( '(' args ')' ) ?) + ) ?
|
|
985 |
; |
|
986 |
||
987 |
'code\_thms' ( constexpr + ) ? |
|
988 |
; |
|
989 |
||
990 |
'code\_deps' ( constexpr + ) ? |
|
991 |
; |
|
992 |
||
993 |
const: term |
|
994 |
; |
|
995 |
||
996 |
constexpr: ( const | 'name.*' | '*' ) |
|
997 |
; |
|
998 |
||
999 |
typeconstructor: nameref |
|
1000 |
; |
|
1001 |
||
1002 |
class: nameref |
|
1003 |
; |
|
1004 |
||
1005 |
target: 'OCaml' | 'SML' | 'Haskell' |
|
1006 |
; |
|
1007 |
||
1008 |
'code\_datatype' const + |
|
1009 |
; |
|
1010 |
||
1011 |
'code\_const' (const + 'and') \\ |
|
1012 |
( ( '(' target ( syntax ? + 'and' ) ')' ) + )
|
|
1013 |
; |
|
1014 |
||
1015 |
'code\_type' (typeconstructor + 'and') \\ |
|
1016 |
( ( '(' target ( syntax ? + 'and' ) ')' ) + )
|
|
1017 |
; |
|
1018 |
||
1019 |
'code\_class' (class + 'and') \\ |
|
1020 |
( ( '(' target \\
|
|
1021 |
( ( string ('where' \\
|
|
1022 |
( const ( '==' | equiv ) string ) + ) ? ) ? + 'and' ) ')' ) + ) |
|
1023 |
; |
|
1024 |
||
1025 |
'code\_instance' (( typeconstructor '::' class ) + 'and') \\ |
|
1026 |
( ( '(' target ( '-' ? + 'and' ) ')' ) + )
|
|
1027 |
; |
|
1028 |
||
1029 |
'code\_monad' const const target |
|
1030 |
; |
|
1031 |
||
1032 |
'code\_reserved' target ( string + ) |
|
1033 |
; |
|
1034 |
||
1035 |
'code\_include' target ( string ( string | '-') ) |
|
1036 |
; |
|
1037 |
||
1038 |
'code\_modulename' target ( ( string string ) + ) |
|
1039 |
; |
|
1040 |
||
1041 |
'code\_exception' ( const + ) |
|
1042 |
; |
|
1043 |
||
1044 |
syntax: string | ( 'infix' | 'infixl' | 'infixr' ) nat string |
|
1045 |
; |
|
1046 |
||
1047 |
'code' ('func' | 'inline') ( 'del' )?
|
|
1048 |
; |
|
1049 |
\end{rail}
|
|
1050 |
||
1051 |
\begin{descr}
|
|
1052 |
||
1053 |
\item [\mbox{\isa{\isacommand{export{\isacharunderscore}code}}}] is the canonical interface
|
|
1054 |
for generating and serializing code: for a given list of constants, |
|
1055 |
code is generated for the specified target languages. Abstract code |
|
1056 |
is cached incrementally. If no constant is given, the currently |
|
1057 |
cached code is serialized. If no serialization instruction is |
|
1058 |
given, only abstract code is cached. |
|
1059 |
||
1060 |
Constants may be specified by giving them literally, referring to |
|
1061 |
all executable contants within a certain theory by giving \isa{{\isachardoublequote}name{\isachardot}{\isacharasterisk}{\isachardoublequote}}, or referring to \emph{all} executable constants currently
|
|
1062 |
available by giving \isa{{\isachardoublequote}{\isacharasterisk}{\isachardoublequote}}.
|
|
1063 |
||
1064 |
By default, for each involved theory one corresponding name space |
|
1065 |
module is generated. Alternativly, a module name may be specified |
|
1066 |
after the \mbox{\isa{\isakeyword{module{\isacharunderscore}name}}} keyword; then \emph{all} code is
|
|
1067 |
placed in this module. |
|
1068 |
||
1069 |
For \emph{SML} and \emph{OCaml}, the file specification refers to a
|
|
1070 |
single file; for \emph{Haskell}, it refers to a whole directory,
|
|
1071 |
where code is generated in multiple files reflecting the module |
|
1072 |
hierarchy. The file specification ``\isa{{\isachardoublequote}{\isacharminus}{\isachardoublequote}}'' denotes standard
|
|
1073 |
output. For \emph{SML}, omitting the file specification compiles
|
|
1074 |
code internally in the context of the current ML session. |
|
1075 |
||
1076 |
Serializers take an optional list of arguments in parentheses. For |
|
1077 |
\emph{Haskell} a module name prefix may be given using the ``\isa{{\isachardoublequote}root{\isacharcolon}{\isachardoublequote}}'' argument; ``\isa{string{\isacharunderscore}classes}'' adds a ``\verb|deriving (Read, Show)|'' clause to each appropriate datatype
|
|
1078 |
declaration. |
|
1079 |
||
1080 |
\item [\mbox{\isa{\isacommand{code{\isacharunderscore}thms}}}] prints a list of theorems
|
|
1081 |
representing the corresponding program containing all given |
|
1082 |
constants; if no constants are given, the currently cached code |
|
1083 |
theorems are printed. |
|
1084 |
||
1085 |
\item [\mbox{\isa{\isacommand{code{\isacharunderscore}deps}}}] visualizes dependencies of
|
|
1086 |
theorems representing the corresponding program containing all given |
|
1087 |
constants; if no constants are given, the currently cached code |
|
1088 |
theorems are visualized. |
|
1089 |
||
1090 |
\item [\mbox{\isa{\isacommand{code{\isacharunderscore}datatype}}}] specifies a constructor set
|
|
1091 |
for a logical type. |
|
1092 |
||
1093 |
\item [\mbox{\isa{\isacommand{code{\isacharunderscore}const}}}] associates a list of constants
|
|
1094 |
with target-specific serializations; omitting a serialization |
|
1095 |
deletes an existing serialization. |
|
1096 |
||
1097 |
\item [\mbox{\isa{\isacommand{code{\isacharunderscore}type}}}] associates a list of type
|
|
1098 |
constructors with target-specific serializations; omitting a |
|
1099 |
serialization deletes an existing serialization. |
|
1100 |
||
1101 |
\item [\mbox{\isa{\isacommand{code{\isacharunderscore}class}}}] associates a list of classes
|
|
1102 |
with target-specific class names; in addition, constants associated |
|
1103 |
with this class may be given target-specific names used for instance |
|
1104 |
declarations; omitting a serialization deletes an existing |
|
1105 |
serialization. This applies only to \emph{Haskell}.
|
|
1106 |
||
1107 |
\item [\mbox{\isa{\isacommand{code{\isacharunderscore}instance}}}] declares a list of type
|
|
1108 |
constructor / class instance relations as ``already present'' for a |
|
1109 |
given target. Omitting a ``\isa{{\isachardoublequote}{\isacharminus}{\isachardoublequote}}'' deletes an existing
|
|
1110 |
``already present'' declaration. This applies only to |
|
1111 |
\emph{Haskell}.
|
|
1112 |
||
1113 |
\item [\mbox{\isa{\isacommand{code{\isacharunderscore}monad}}}] provides an auxiliary
|
|
1114 |
mechanism to generate monadic code. |
|
1115 |
||
1116 |
\item [\mbox{\isa{\isacommand{code{\isacharunderscore}reserved}}}] declares a list of names as
|
|
1117 |
reserved for a given target, preventing it to be shadowed by any |
|
1118 |
generated code. |
|
1119 |
||
1120 |
\item [\mbox{\isa{\isacommand{code{\isacharunderscore}include}}}] adds arbitrary named content
|
|
1121 |
(``include'') to generated code. A as last argument ``\isa{{\isachardoublequote}{\isacharminus}{\isachardoublequote}}''
|
|
1122 |
will remove an already added ``include''. |
|
1123 |
||
1124 |
\item [\mbox{\isa{\isacommand{code{\isacharunderscore}modulename}}}] declares aliasings from
|
|
1125 |
one module name onto another. |
|
1126 |
||
1127 |
\item [\mbox{\isa{\isacommand{code{\isacharunderscore}exception}}}] declares constants which
|
|
1128 |
are not required to have a definition by a defining equations; these |
|
1129 |
are mapped on exceptions instead. |
|
1130 |
||
1131 |
\item [\mbox{\isa{code}}~\isa{func}] explicitly selects (or
|
|
1132 |
with option ``\isa{{\isachardoublequote}del{\isacharcolon}{\isachardoublequote}}'' deselects) a defining equation for
|
|
1133 |
code generation. Usually packages introducing defining equations |
|
1134 |
provide a resonable default setup for selection. |
|
1135 |
||
1136 |
\item [\mbox{\isa{code}}\isa{inline}] declares (or with
|
|
1137 |
option ``\isa{{\isachardoublequote}del{\isacharcolon}{\isachardoublequote}}'' removes) inlining theorems which are
|
|
1138 |
applied as rewrite rules to any defining equation during |
|
1139 |
preprocessing. |
|
1140 |
||
1141 |
\item [\mbox{\isa{\isacommand{print{\isacharunderscore}codesetup}}}] gives an overview on
|
|
1142 |
selected defining equations, code generator datatypes and |
|
1143 |
preprocessor setup. |
|
1144 |
||
1145 |
\end{descr}%
|
|
1146 |
\end{isamarkuptext}%
|
|
1147 |
\isamarkuptrue% |
|
1148 |
% |
|
1149 |
\isadelimtheory |
|
1150 |
% |
|
1151 |
\endisadelimtheory |
|
1152 |
% |
|
1153 |
\isatagtheory |
|
| 26840 | 1154 |
\isacommand{end}\isamarkupfalse%
|
1155 |
% |
|
1156 |
\endisatagtheory |
|
1157 |
{\isafoldtheory}%
|
|
1158 |
% |
|
1159 |
\isadelimtheory |
|
1160 |
% |
|
1161 |
\endisadelimtheory |
|
| 26849 | 1162 |
\isanewline |
1163 |
\isanewline |
|
| 26840 | 1164 |
\end{isabellebody}%
|
1165 |
%%% Local Variables: |
|
1166 |
%%% mode: latex |
|
1167 |
%%% TeX-master: "root" |
|
1168 |
%%% End: |