From b63444d91966eeb11ff244327555def31fe5ffb0 Mon Sep 17 00:00:00 2001
From: Jan Nieuwenhuizen <janneke@gnu.org>
Date: Sat, 23 Jul 2016 11:51:06 +0200
Subject: [PATCH] mes.c: barf on unknown symbols.

---
 mes.c      |  7 ++++++-
 scm.mes    |  2 ++
 syntax.mes | 30 +++++++-----------------------
 3 files changed, 15 insertions(+), 24 deletions(-)

diff --git a/mes.c b/mes.c
index 80cd827e..d4f1a165 100644
--- a/mes.c
+++ b/mes.c
@@ -309,7 +309,7 @@ eval (scm *e, scm *a)
   if (e->type == SYMBOL) {
     scm *y = assq (e, a);
     if (y == &scm_f) {
-      return e;
+      //return e;
       printf ("eval: no such symbol: %s\n", e->name);
       assert (!"unknown symbol");
     }
@@ -1108,6 +1108,11 @@ mes_environment ()
 {
   scm *a = &scm_nil;
 
+  a = cons (cons (&scm_f, &scm_f), a);
+  a = cons (cons (&scm_nil, &scm_nil), a);
+  a = cons (cons (&scm_t, &scm_t), a);
+  a = cons (cons (&scm_unspecified, &scm_unspecified), a);
+  
 #include "environment.i"
   
   return a;
diff --git a/scm.mes b/scm.mes
index 0382dfb4..edfa8bdc 100755
--- a/scm.mes
+++ b/scm.mes
@@ -199,6 +199,8 @@
         (set! counter (+ counter 1))
         (string->symbol (string-append "g" value))))))
 
+
+()
 ;; srfi-1
 (define (last-pair lst)
   (let loop ((lst lst))
diff --git a/syntax.mes b/syntax.mes
index ebc7faee..6232fce7 100644
--- a/syntax.mes
+++ b/syntax.mes
@@ -41,7 +41,7 @@
 
 (display "mes:define-syntax...")
 
-(define-macro (mes:define-syntax macro-name transformer . stuff)
+(define-macro (define-syntax macro-name transformer . stuff)
   `(define-macro (,macro-name . args)
      (,transformer (cons ',macro-name args)
                              (lambda (x) x)
@@ -63,7 +63,7 @@
 (display "mes:define-syntax syntax-rules...")
 (newline)
 
-(mes:define-syntax syntax-rules
+(define-syntax syntax-rules
    (let ()
      (define name? symbol?)
 
@@ -242,25 +242,9 @@
 
       (make-transformer rules))))
 
+(define-macro (define-syntax-rule id-pattern . template)
+  `(define-syntax ,(car id-pattern)
+     (syntax-rules ()
+       ((,(car id-pattern) . ,(cdr id-pattern)) ,@template))))
 
-(mes:define-syntax mes:or
-  (syntax-rules ()
-    ((mes:or) #f)
-    ((mes:or e) e)
-    ((mes:or e1 e ...) (let ((temp e1))
-                         (cond (temp temp) (#t (or e ...)))))))
-
-(display "(mes:or #f (= 0 1) 'hello-syntax-world): ")
-(display (mes:or #f (= 0 1) 'hello-syntax-world))
-(display (mes:or #f '==>baaa))
-(newline)
-
-(mes:define-syntax mes:when
-  (syntax-rules ()
-    ((when condition exp ...)
-     (if condition
-         (begin exp ...)))))
-
-(display (mes:when #t "when:hello syntax world"))
-(newline)
-'syntax-dun
+(define else #t)