tisp

commit ad9fddcee09a0b17330ae632f7e77978ba14fbcb
parent 71245640e69ee80bba56fe634b3ab1ed0880a135
Author: Ed van Bruggen <edvb@uw.edu>
Date:   Tue, 15 Oct 2019 17:36:47 -0700

cond return void not nil if no conditions are met

Diffstat:
test.c
 | 
6
+++---
tibs/lib.tsp
 | 
4
++--
tisp.c
 | 
2
+-

3 files changed, 6 insertions(+), 6 deletions(-)
diff --git a/test.c b/test.c
@@ -118,14 +118,14 @@ char *tests[][2] = {
 	{ "(do (define bar '(/ 25 5)) (eval bar))", "5"         },
 
 	{ "cond",                                          NULL },
-	{ "(cond)",                                        "()" },
+	{ "(cond)",                                        "" },
 	{ "(cond (t 1))",                                  "1"  },
 	{ "(cond ((= 1 1) 1) ((= 1 2) 2) (t 3))",          "1"  },
 	{ "(cond ((= 1 2) 1) ((= 1 2) 2) (else (+ 1 2)))", "3"  },
 	{ "(cond ((= 1 2) 1) ((= 1 1) 2) (else 3))",       "2"  },
-	{ "(cond ((= 1 2) 1) ((= 1 3) 2))",                "()" },
+	{ "(cond ((= 1 2) 1) ((= 1 3) 2))",                "" },
 	{ "(cond ((= 1 2) 1) (\"foo\" 2) (else 3))",       "2"  },
-	{ "(cond (() (+ 1 2)))",                           "()" },
+	{ "(cond (() (+ 1 2)))",                           "" },
 
 	{ "eq",                                          NULL },
 	{ "(=)",                                         "t"  },
diff --git a/tibs/lib.tsp b/tibs/lib.tsp
@@ -58,10 +58,10 @@
 (define else t)
 (define when
   (macro (con . body)
-         (list 'cond (list con (cons 'do body)) (list t (void)))))
+         (list 'cond (list con (cons 'do body)))))
 (define unless
   (macro (con . body)
-         (list 'cond (list con (void)) (list t (cons 'do body)))))
+         (list 'cond (list (list not con) (cons 'do body)))))
 (define let
   (macro (vars . body)
          (cons (list* 'lambda (map car vars) body) (map cadr vars))))
diff --git a/tisp.c b/tisp.c
@@ -890,7 +890,7 @@ prim_cond(Env env, Val args)
 			return NULL;
 		else if (!nilp(cond))
 			return tisp_eval(env, car(cdar(v)));
-	return env->nil;
+	return env->none;
 }
 
 /* return type of tisp value */