--- a/CookBook/Recipes/Antiquotes.thy Thu Jan 15 13:42:28 2009 +0000
+++ b/CookBook/Recipes/Antiquotes.thy Fri Jan 16 14:57:36 2009 +0000
@@ -15,18 +15,21 @@
Document antiquotations can be used for ensuring consistent type-setting of
various entities in a document. They can also be used for sophisticated
\LaTeX-hacking. If you type @{text "Ctrl-c Ctrl-a h A"} inside ProofGeneral, you
- obtain a list of all available document antiquotations and their options.
+ obtain a list of all currently available document antiquotations and their options.
Below we give the code for two additional antiquotations that can be used to typeset
ML-code and also to check whether the given code actually compiles. This
provides a sanity check for the code and also allows one to keep documents
in sync with other code, for example Isabelle.
- We first describe the antiquotation @{text "@{ML_checked \"expr\"}"}. This
- antiquotation takes a piece of code as argument. The code is checked
- by sending the ML-expression @{text [quotes] "val _ = \<dots>"} containing the
- given argument to the ML-compiler (i.e.~the function @{ML "ML_Context.eval_in"}
- in Line 4 below). The complete code of the antiquotation is as follows:
+ We first describe the antiquotation @{text "ML_checked"} with the syntax:
+
+ @{text [display] "@{ML_checked \"a_piece_of_code\"}"}
+
+ The code is checked by sending the ML-expression @{text [quotes] "val _ =
+ a_piece_of_code"} to the ML-compiler (i.e.~the function @{ML
+ "ML_Context.eval_in"} in Line 4 below). The complete code of the
+ antiquotation is as follows:
*}
@@ -44,16 +47,16 @@
Note that the parser @{ML "(Scan.lift Args.name)"} in line 9 parses a string,
in this case the code given as argument. As mentioned before, this argument
- is send to the ML-compiler in the line 4 using the function @{ML ml_val},
- which constructs an apropriate ML-expression.
+ is sent to the ML-compiler in the line 4 using the function @{ML ml_val},
+ which constructs the appropriate ML-expression.
If the code is ``approved'' by the compiler, then the output function @{ML
"ThyOutput.output_list (fn _ => fn s => Pretty.str s)"} in the next line pretty prints the
code. This function expects that the code is a list of strings where each
string correspond to a line in the output. Therefore the use of
@{ML "(space_explode \"\\n\" txt)" for txt}
which produces this list according to linebreaks. There are a number of options for antiquotations
- that are observed by @{ML ThyOutput.output_list} when printing the code (for
- example @{text "[display]"}, @{text "[quotes]"} and @{text "[source]"}).
+ that are observed by @{ML ThyOutput.output_list} when printing the code (including
+ @{text "[display]"}, @{text "[quotes]"} and @{text "[source]"}).
\begin{readmore}
For more information about options of antiquotations see \rsccite{sec:antiq}).
@@ -62,7 +65,6 @@
Since we used the argument @{ML "Position.none"}, the compiler cannot give specific
information about the line number, in case an error is detected. We
can improve the code above slightly by writing
-
*}
ML%linenumbers{*fun output_ml src ctxt (code_txt,pos) =
@@ -84,22 +86,24 @@
somebody changes the definition of \mbox{@{ML "(op +)"}}.
- The second antiquotation extends the first by allowing also to give
- hints what the result of the ML-code should be and to check the consistency of
- the actual result with these hints. For this we are going to implement the
- antiquotation
- @{text "@{ML_resp \"expr\" \"pat\"}"}
- whose first argument is the ML-code and the second is a pattern specifying
- the result. To add some convenience and allow dealing with large outputs,
- the user can give a partial specification including abbreviations
- @{text [quotes] "\<dots>"}.
+ The second antiquotation we describe extends the first by allowing also to give
+ a pattern that specifies what the result of the ML-code should be and to check
+ the consistency of the actual result with the given pattern. For this we are going
+ to implement the antiquotation
+
+ @{text [display] "@{ML_resp \"a_piece_of_code\" \"pattern\"}"}
+
+ To add some convenience and also to deal with large outputs,
+ the user can give a partial specification by giving the abbreviation
+ @{text [quotes] "\<dots>"}. For example @{text "(\<dots>,\<dots>)"} for a pair.
- Whereas in the antiquotation @{text "@{ML_checked \"expr\"}"} above, we have
- sent the expression
- @{text [quotes] "val _ = expr"} to the compiler, in this antiquotation the wildcard
- @{text "_"} we will be replaced by a proper pattern constructed the hints. To
- do this we need to replace the @{text [quotes] "\<dots>"} by @{text [quotes] "_"}
- before sending the code to the compiler. The following function will do this:
+ Whereas in the antiquotation @{text "@{ML_checked \"piece_of_code\"}"} above,
+ we have sent the expression
+ @{text [quotes] "val _ = piece_of_code"} to the compiler, in the second the
+ wildcard @{text "_"} we will be replaced by a proper pattern. To do this we
+ need to replace the @{text [quotes] "\<dots>"} by
+ @{text [quotes] "_"} before sending the code to the compiler. The following
+ function will do this:
*}
@@ -154,8 +158,8 @@
@{ML_resp [display] "let val i = 3 in (i * i,\"foo\") end" "(9,\<dots>)"}
In both cases, the check by the compiler ensures that code and result match. A limitation
- of this antiquotation is that the hints can only be given for results that can actually
- be constructed as a pattern. This excludes values that are abstract datatypes, like
+ of this antiquotation, however, is that the hints can only be given in case
+ they can be constructed as a pattern. This excludes values that are abstract datatypes, like
theorems or cterms.
*}