'and' macro example

nishio · Jun 17, 2012 · e57593b · e57593b
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diff --git a/test.html b/test.html
@@ -63,6 +63,16 @@
       (cons (func (car list))
             (map func (cdr list)))))
 (map (lambda (x) (+ x 1)) '(1 2 3))
+
+; And macro example
+(defmacro (and x . xs)
+  (if (empty? xs)
+      x
+      `(when ,x (and . ,xs))))
+(expand-code '(and a b c d))
+; and to demonstrate the short-circuit mechanism:
+; ((unknown) should crash when run)
+(and (= 2 2) (= 2 3) (unknown))
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