core: Remove string.c.

* string.c: Remove.
* mes.c (eval_apply): Remove caller.
* GNUmakefile (mes.o): Remove dependency on string.
* module/mes/psyntax-0.mes (eval): Handle "noexpand".
* module/mes/type-0.mes (string->symbol, symbol->list, symbol->string):
  New function.

GNUmakefile

@@ -34,7 +34,6 @@ mes.o: lib.c lib.h lib.i lib.environment.i
 mes.o: math.c math.h math.i math.environment.i
 mes.o: posix.c posix.h posix.i posix.environment.i
 mes.o: reader.c reader.h reader.i reader.environment.i
-mes.o: string.c string.h string.i string.environment.i
 
 clean:
 	rm -f mes mes.o *.environment.i *.symbols.i *.environment.h *.cat a.out

mes.c

@@ -157,7 +157,6 @@ SCM r3 = 0; // param 3
 #include "mes.h"
 #include "posix.h"
 #include "reader.h"
-#include "string.h"
 
 #define CAR(x) g_cells[x].car
 #define CDR(x) g_cells[x].cdr
@@ -507,12 +506,9 @@ eval_apply ()
     default: return r1;
     }
 
- macro_expand:
-  if (TYPE (CAR (r1)) == STRING && string_to_symbol (CAR (r1)) == cell_symbol_noexpand)
-    return cadr (r1);
-
   SCM macro;
   SCM expanders;
+ macro_expand:
   if (TYPE (r1) == PAIR
       && (macro = lookup_macro (car (r1), r0)) != cell_f)
     {
@@ -1087,7 +1083,6 @@ mes_builtins (SCM a)
 #include "math.i"
 #include "posix.i"
 #include "reader.i"
-#include "string.i"
 
 #include "display.environment.i"
 #include "lib.environment.i"
@@ -1095,7 +1090,6 @@ mes_builtins (SCM a)
 #include "mes.environment.i"
 #include "posix.environment.i"
 #include "reader.environment.i"
-#include "string.environment.i"
 
   return a;
 }
@@ -1211,7 +1205,6 @@ dump ()
 #include "math.c"
 #include "posix.c"
 #include "reader.c"
-#include "string.c"
 
 int
 main (int argc, char *argv[])

module/mes/psyntax-0.mes

@@ -21,7 +21,8 @@
 (define (interaction-environment) (current-module))
 
 (define (eval x . environment)
-  (eval-env x (if (null? environment) (current-module) (car environment))))
+  (eval-env (if (and (pair? x) (equal? (car x) "noexpand")) (cadr x) x)
+            (if (null? environment) (current-module) (car environment))))
 
 (define annotation? (lambda (x) #f))
 (define (self-evaluating? x)

module/mes/type-0.mes

@@ -120,5 +120,15 @@
 (define (string->list s)
   (core:car s))
 
+(define (string->symbol s)
+  (if (not (pair? (core:car s))) '()
+      (make-symbol (core:car s))))
+
+(define (symbol->list s)
+  (core:car s))
+
+(define (symbol->string s)
+  (apply string (symbol->list s)))
+
 (define (string-append . rest)
   (apply string (apply append (map1 string->list rest))))

string.c

@@ -1,48 +0,0 @@
-/* -*-comment-start: "//";comment-end:""-*-
- * Mes --- Maxwell Equations of Software
- * Copyright © 2016 Jan Nieuwenhuizen <janneke@gnu.org>
- *
- * This file is part of Mes.
- *
- * Mes is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 3 of the License, or (at
- * your option) any later version.
- *
- * Mes is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with Mes.  If not, see <http://www.gnu.org/licenses/>.
- */
-
-SCM
-string_to_symbol (SCM x)
-{
-  assert (TYPE (x) == STRING);
-  return STRING (x) == cell_nil ? cell_nil : make_symbol (STRING (x));
-}
-
-SCM
-symbol_to_string (SCM x)
-{
-  assert (TYPE (x) == SYMBOL);
-  return MAKE_STRING (STRING (x));
-}
-
-SCM
-keyword_to_symbol (SCM x)
-{
-  assert (TYPE (x) == KEYWORD);
-  return make_symbol (STRING (x));
-}
-
-SCM
-symbol_to_keyword (SCM x)
-{
-  assert (TYPE (x) == SYMBOL);
-  g_cells[tmp_num].value = KEYWORD;
-  return make_cell (tmp_num, STRING (x), 0);
-}