typemap m3wrapargconst allow definition of local constants

git-svn-id: https://swig.svn.sourceforge.net/svnroot/swig/trunk/SWIG@6617 626c5289-ae23-0410-ae9c-e8d60b6d4f22

Doc/Manual/Modula3.html

@@ -146,7 +146,7 @@ On the one hand Modula-3 can be safe
 while providing much static and dynamic safety.
 On the other hand you can write efficient
 but less safe code in the style of C
-within UNSAFE modules.
+within <tt>UNSAFE</tt> modules.
 
 <p>
 Unfortunately Modula's safety and strength
@@ -187,7 +187,7 @@ and the low level of the C libraries.
 SWIG converts C headers to Modula-3 interfaces for you.
 You could call the C functions without loss
 of efficiency but it won't be joy
-because you could not pass TEXTs
+because you could not pass <tt>TEXT</tt>s
 or open arrays and
 you would have to process error return codes
 rather then exceptions.
@@ -650,11 +650,18 @@ consist of the following parts:
 </tr>
 <tr>
   <td>m3wrapargvar</td>
-  <td><tt>$1: Ptr := $1_name;</tt></td>
+  <td><tt>$1: INTEGER := $1_name;</tt></td>
   <td>
     Declaration of some variables needed for temporary results.
   </td>
 </tr>
+<tr>
+  <td>m3wrapargconst</td>
+  <td><tt>$1 = "$1_name";</tt></td>
+  <td>
+    Declaration of some constant, maybe for debug purposes.
+  </td>
+</tr>
 <tr>
   <td>m3wrapargraw</td>
   <td><tt>ORD($1_name)</tt></td>
@@ -909,6 +916,8 @@ where almost everything is generated by a typemap:
   PROCEDURE Name     (READONLY       str       :    TEXT    :=      ""       )
 <I>              (* m3wrapoutcheck:throws *)</I>
      : NameResult RAISES {E} =
+    CONST
+      arg1name = "str";                  <I>(* m3wrapargconst *)</I>
     VAR
       arg0   : C.char_star;              <I>(* m3wrapretvar *)</I>
       arg1   : C.char_star;              <I>(* m3wrapargvar *)</I>

Source/Modules/modula3.cxx

@@ -23,12 +23,12 @@ char cvsroot_modula3_cxx[] =
      It's not a good concept to use functions of superclasses for specific services.
      E.g. For SWIG this means: Generating accessor functions for member variables
      is the most common but no general task to be processed in membervariableHandler.
-     Better provide a service functions which generates accessor function code
+     Better provide a service function which generates accessor function code
      and equip this service function with all parameters needed for input (parse node)
      and output (generated code).
    - How can I make globalvariableHandler not to generate
      interface functions to two accessor functions
-     (that don't exist)
+     (that don't exist) ?
    - How can I generate a typemap that turns every C reference argument into
      its Modula 3 counterpart, that is
        void test(Complex &z);
@@ -3292,6 +3292,7 @@ MODULA3 ():
     String *rawcall = NewString ("");
     String *reccall = NewString ("");
     String *local_variables = NewString ("");
+    String *local_constants = NewString ("");
     String *incheck = NewString ("");
     String *outcheck = NewString ("");
     String *setup = NewString ("");
@@ -3316,6 +3317,7 @@ MODULA3 ():
 
     /* Attach the non-standard typemaps to the parameter list */
     Swig_typemap_attach_parms ("m3wrapargvar", l, NULL);
+    Swig_typemap_attach_parms ("m3wrapargconst", l, NULL);
     Swig_typemap_attach_parms ("m3wrapargraw", l, NULL);
     Swig_typemap_attach_parms ("m3wrapargdir", l, NULL);
     Swig_typemap_attach_parms ("m3wrapinmode", l, NULL);
@@ -3429,6 +3431,26 @@ MODULA3 ():
       }
     }
 
+    /* Declare local constants e.g. for storing argument names. */
+    {
+      Parm *p = l;
+      while (p != NIL) {
+
+        String *arg = Getattr (p, "autoname");
+
+        String *tm = Getattr (p, "tmap:m3wrapargconst");
+        if (tm != NIL) {
+          addImports (m3wrap_impl.import, "m3wrapargconst", p);
+          Replaceall (tm, "$input", arg);
+          Printv (local_constants, tm, "\n", NIL);
+          p = Getattr (p, "tmap:m3wrapargconst:next");
+        } else {
+          p = nextSibling (p);
+        }
+
+      }
+    }
+
     /* Declare local variables e.g. for converted input values. */
     {
       String *tm = getMappedTypeNew (n, "m3wrapretvar", "", false);
@@ -3722,9 +3744,10 @@ MODULA3 ():
         exc_handler = NewStringf ("%s%s", body, cleanup);
       }
 
-      Printf (function_code, " =\n%s%sBEGIN\n%s%sEND %s;\n\n",
-              hasContent (local_variables) ? "VAR\n" : "",
-              local_variables, exc_handler, outarg, func_name);
+      Printf (function_code, " =\n%s%s%s%sBEGIN\n%s%sEND %s;\n\n",
+              hasContent (local_constants) ? "CONST\n" : "", local_constants,
+              hasContent (local_variables) ? "VAR\n"   : "", local_variables,
+              exc_handler, outarg, func_name);
 
       Delete (exc_handler);
       Delete (body);
@@ -3771,6 +3794,7 @@ MODULA3 ():
     Delete (arguments);
     Delete (return_variables);
     Delete (local_variables);
+    Delete (local_constants);
     Delete (outarg);
     Delete (incheck);
     Delete (outcheck);