Added and and or

lispy.c

@@ -1118,12 +1118,32 @@ object *eval(object *exp, object *env) {
 
   /**  and  **/
   else if (is_primitive_syntax(exp, and_symbol)) {
-    error("and not implemented yet");
+    exp = cdr(exp);
+    while (!is_last_exp(exp)) {
+      if (eval(car(exp), env) != False) {
+        exp = cdr(exp);
+      }
+      else {
+        return False;
+      }
+    }
+    return car(exp);
   }
 
   /**  or  **/
   else if (is_primitive_syntax(exp, or_symbol)) {
-    error("or not implemented yet");
+    object *result;
+    exp = cdr(exp);
+    while (exp != the_empty_list) {
+      result = eval(car(exp), env);
+      if (result == False) {
+        exp = cdr(exp);
+      }
+      else {
+        return result;
+      }
+    }
+    return False;
   }
 
   /**  apply  **/

unit_test.lispy

@@ -296,6 +296,30 @@
 )
 
 
+;;  and
+;;_________________________;;
+
+(test
+  (and 1 2 3)
+  >>> 3
+  (and 1 False 2)
+  >>> False
+)
+
+
+;;  or
+;;_________________________;;
+
+(test
+  (or 1 2)
+  >>> 1
+  (or False 2)
+  >>> 2
+  (or False False)
+  >>> False
+)
+
+
 ;;  apply
 ;;_________________________;;