core: Add getenv, verbose module loading on MES_DEBUG.

* mes.c (MAKE_REF, MAKE_STRING): Oops, remove stray semicolon.
* posix.c (getenv_): New function.
* module/mes/base-0.mes (load): Use it to switch on MES_DEBUG=1.
  (mes-use-module): Remove commented-out code.

mes.c

@@ -163,8 +163,8 @@ SCM r3 = 0; // param 3
 
 #define MAKE_CHAR(n) make_cell (tmp_num_ (CHAR), 0, tmp_num2_ (n))
 #define MAKE_NUMBER(n) make_cell (tmp_num_ (NUMBER), 0, tmp_num2_ (n))
-#define MAKE_REF(n) make_cell (tmp_num_ (REF), n, 0);
-#define MAKE_STRING(x) make_cell (tmp_num_ (STRING), x, 0);
+#define MAKE_REF(n) make_cell (tmp_num_ (REF), n, 0)
+#define MAKE_STRING(x) make_cell (tmp_num_ (STRING), x, 0)
 
 int error (char const* msg, SCM x);
 SCM vm_call (function0_t f, SCM p1, SCM p2, SCM a);

module/mes/base-0.mes

@@ -108,9 +108,11 @@
         'o))
 (define-macro (load file)
   (list 'begin
-          (list core:stderr "read ")
-          (list core:stderr file)
-          (list core:stderr "\n")
+        (list 'if (list getenv "MES_DEBUG")
+              (list 'begin
+                    (list core:stderr "read ")
+                    (list core:stderr file)
+                    (list core:stderr "\n")))
      (list 'push! '*input-ports* (list current-input-port))
      (list 'set-current-input-port (list open-input-file file))
      (list 'primitive-load)
@@ -153,9 +155,6 @@
          (list
           'begin
           (list 'set! '*modules* (list cons (list string->symbol (module->file module)) '*modules*))
-          ;; (list core:stderr "read ")
-          ;; (list core:stderr file)
-          ;; (list core:stderr "\n")
           (list 'load (list string-append '*mes-prefix* (module->file module)))))))
 
 (mes-use-module (srfi srfi-0))

posix.c

@@ -40,6 +40,13 @@ peekchar ()
   return c;
 }
 
+SCM
+getenv_ (SCM s) ///((name . "getenv"))
+{
+  char *p = getenv (string_to_cstring (s));
+  return p ? MAKE_STRING (cstring_to_list (p)) : cell_f;
+}
+
 SCM
 peek_byte ()
 {