diff -r f3794c231898 -r b5914f3c643c CookBook/Recipes/Antiquotes.thy --- a/CookBook/Recipes/Antiquotes.thy Tue Dec 16 17:28:05 2008 +0000 +++ b/CookBook/Recipes/Antiquotes.thy Wed Dec 17 05:08:33 2008 +0000 @@ -22,34 +22,36 @@ 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 argument is checked + antiquotation takes a piece of code as argument. The code is checked by sending the ML-expression @{text [quotes] "val _ = \"} containing the given argument to the ML-compiler (i.e.~the function @{ML "ML_Context.eval_in"} - in Line 4 in the code below). The code of @{text "@{ML_checked \"expr\"}"} - is as follows: + in Line 4 below). The complete code of the antiquotation is as follows: *} -ML %linenumbers {*fun ml_val txt = "val _ = " ^ txt +ML %linenumbers {*fun ml_val code_txt = "val _ = " ^ code_txt -fun output_ml ml src ctxt txt = - (ML_Context.eval_in (SOME ctxt) false Position.none (ml txt); +fun output_ml src ctxt code_txt = + (ML_Context.eval_in (SOME ctxt) false Position.none (ml_val code_txt); ThyOutput.output_list (fn _ => fn s => Pretty.str s) src ctxt - (space_explode "\n" txt)) + (space_explode "\n" code_txt)) val _ = ThyOutput.add_commands - [("ML_checked", ThyOutput.args (Scan.lift Args.name) (output_ml ml_val))] + [("ML_checked", ThyOutput.args (Scan.lift Args.name) output_ml)] *} text {* Note that the parser @{ML "(Scan.lift Args.name)"} in line 9 parses a string, - in this case the code given as argument. This argument is send to the ML-compiler in the line 4. + 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. 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. Therefore the @{ML "(space_explode \"\\n\" txt)" for txt} - which produces this list. There are a number of options for antiquotations + 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]"}). @@ -58,19 +60,19 @@ \end{readmore} Since we used the argument @{ML "Position.none"}, the compiler cannot give specific - information about the line number where an error might have occurred. We - can improve this code slightly by writing + 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 ml src ctxt (txt,pos) = - (ML_Context.eval_in (SOME ctxt) false pos (ml txt); +ML %linenumbers {* fun output_ml src ctxt (code_txt,pos) = + (ML_Context.eval_in (SOME ctxt) false pos (ml_val code_txt); ThyOutput.output_list (fn _ => fn s => Pretty.str s) src ctxt - (space_explode "\n" txt)) + (space_explode "\n" code_txt)) val _ = ThyOutput.add_commands [("ML_checked", ThyOutput.args - (Scan.lift (OuterParse.position Args.name)) (output_ml ml_val))] + (Scan.lift (OuterParse.position Args.name)) output_ml)] *} text {* @@ -84,36 +86,41 @@ The second antiquotation extends the first by allowing also to give - hints what the result of the ML-code is and check the consistency of - the actual result with these hints. For this we use the antiquotation + 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_response \"expr\" \"pat\"}"} whose first argument is the ML-code and the second is a pattern specifying - the result. To add some convenience we allow the user to give a partial - specification using @{text "\"}. + the result. To add some convenience and allow dealing with large outputs, + the user can give a partial specification including abbreviations + @{text [quotes] "\"}. - In the antiquotation @{text "@{ML_checked \"expr\"}"} we send the expression - @{text [quotes] "val _ = expr"} to the compiler. Instead of the wildcard - @{text "_"}, we will here use the hints to construct a proper pattern. To - do this we need to replace the @{text "\"} by @{text "_"} before sending the - code to the compiler. The function + 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] "\"} by @{text [quotes] "_"} + before sending the code to the compiler. The following function will do this: *} ML {* -fun ml_pat (rhs, pat) = -let val pat' = implode (map (fn "\" => "_" | s => s) (Symbol.explode pat)) -in "val " ^ pat' ^ " = " ^ rhs end; +fun ml_pat (code_txt, pat) = + let val pat' = + implode (map (fn "\" => "_" | s => s) (Symbol.explode pat)) + in + "val " ^ pat' ^ " = " ^ code_txt + end *} text {* - will construct the pattern that the compiler can use. Next we like to add - a response indicator to the result using: + Next we like to add a response indicator to the result using: *} ML {* -fun add_response_indicator txt = - map (fn s => "> " ^ s) (space_explode "\n" txt) +fun add_response_indicator pat = + map (fn s => "> " ^ s) (space_explode "\n" pat) *} text {* @@ -121,16 +128,19 @@ *} ML {* -fun output_ml_response ml src ctxt ((lhs,pat),pos) = - (ML_Context.eval_in (SOME ctxt) false pos (ml (lhs,pat)); - let val txt = (space_explode "\n" lhs) @ (add_response_indicator pat) - in ThyOutput.output_list (fn _ => fn s => Pretty.str s) src ctxt txt end) +fun output_ml_response src ctxt ((code_txt,pat),pos) = + (ML_Context.eval_in (SOME ctxt) false pos (ml_pat (code_txt,pat)); + let + val output = (space_explode "\n" code_txt) @ (add_response_indicator pat) + in + ThyOutput.output_list (fn _ => fn s => Pretty.str s) src ctxt output + end) val _ = ThyOutput.add_commands [("ML_response", ThyOutput.args (Scan.lift (OuterParse.position (Args.name -- Args.name))) - (output_ml_response ml_pat))] + output_ml_response)] *} text {*