--- stack/stack.c	2003/08/11 14:31:48	1.133
+++ stack/stack.c	2003/08/13 11:58:00	1.135
@@ -23,7 +23,7 @@
 
 #include "stack.h"
 
-const char* start_message= "Stack version $Revision: 1.133 $\n\
+const char* start_message= "Stack version $Revision: 1.135 $\n\
 Copyright (C) 2002  Mats Alritzson and Teddy Hogeborn\n\
 Stack comes with ABSOLUTELY NO WARRANTY; for details type 'warranty;'.\n\
 This is free software, and you are welcome to redistribute it\n\
@@ -50,8 +50,27 @@
 }
 
 
-void printerr(environment *env, const char* in_string)
+void printerr(environment *env)
 {
+  char *in_string;
+
+  switch(env->err) {
+  case 0:
+    return;
+  case 1:
+    in_string= "Too Few Arguments";
+    break;
+  case 2:
+    in_string= "Bad Argument Type";
+    break;
+  case 3:
+    in_string= "Unbound Variable";
+    break;
+  default:
+    in_string= "Unknown error";
+    break;
+  }
+
   fprintf(stderr, "\"%s\":\nErr: %s\n", env->errsymb, in_string);
 }
 
@@ -585,13 +604,10 @@
 extern void swap(environment *env)
 {
   value *temp= env->head;
-  
-  if(env->head->type == empty || CDR(env->head)->type == empty) {
-    printerr(env, "Too Few Arguments");
-    env->err=1;
-    return;
-  }
 
+  if(check_args(env, unknown, unknown, empty))
+    return printerr(env);
+  
   env->head= CDR(env->head);
   CDR(temp)= CDR(env->head);
   CDR(env->head)= temp;
@@ -603,24 +619,15 @@
 {
   value *val;
 
-  if(env->head->type==empty) {
-    printerr(env, "Too Few Arguments");
-    env->err= 1;
-    return;
-  }
-
-  if(CAR(env->head)->type!=symb) {
-    printerr(env, "Bad Argument Type");
-    env->err= 2;
-    return;
-  }
+  if(check_args(env, symb, empty))
+    return printerr(env);
 
   val= CAR(env->head)->content.sym->val;
   if(val == NULL){
-    printerr(env, "Unbound Variable");
     env->err= 3;
-    return;
+    return printerr(env);
   }
+
   push_val(env, val);		/* Return the symbol's bound value */
   swap(env);
   if(env->err) return;
@@ -641,11 +648,8 @@
 
   gc_maybe(env);
 
-  if(env->head->type==empty) {
-    printerr(env, "Too Few Arguments");
-    env->err= 1;
-    return;
-  }
+  if(check_args(env, unknown, empty))
+    return printerr(env);
 
   switch(CAR(env->head)->type) {
     /* if it's a symbol */
@@ -662,7 +666,7 @@
   case func:
     in_func= CAR(env->head)->content.func;
     env->head= CDR(env->head);
-    return in_func(env);
+    return in_func((void*)env);
 
     /* If it's a list */
   case tcons:
@@ -688,9 +692,8 @@
       if (CDR(iterator)->type == empty || CDR(iterator)->type == tcons) 
 	iterator= CDR(iterator);
       else {
-	printerr(env, "Bad Argument Type"); /* Improper list */
-	env->err= 2;
-	return;
+	env->err= 2; /* Improper list */
+	return printerr(env); 
       }
     }
     unprotect(temp_val);
@@ -759,7 +762,7 @@
   }
 
   if(myenv.interactive)
-    printf(start_message);
+    puts(start_message);
 
   while(1) {
     if(myenv.in_string==NULL) {
@@ -854,20 +857,11 @@
 {
   value *old_head, *new_head, *item;
 
-  if(env->head->type==empty) {
-    printerr(env, "Too Few Arguments");
-    env->err= 1;
-    return;
-  }
-
   if(CAR(env->head)->type==empty)
     return;			/* Don't reverse an empty list */
 
-  if(CAR(env->head)->type!=tcons) {
-    printerr(env, "Bad Argument Type");
-    env->err= 2;
-    return;
-  }
+  if(check_args(env, tcons, empty))
+    return printerr(env);
 
   old_head= CAR(env->head);
   new_head= new_val(env);