X-Git-Url: https://git.jsancho.org/?a=blobdiff_plain;f=src%2Fgacela_misc.scm;fp=src%2Fgacela_misc.scm;h=d486b2650b734a2bea3ef7b977f42898ad7ef480;hb=75d1bbb394aa23715811cac3da7ad6b202df26cf;hp=b75a44eb1cf91a4d1c1158db9c754a5c06687b0a;hpb=9e55bd787fa48db3ce0b8bde5ce40539b301d30a;p=gacela.git

diff --git a/src/gacela_misc.scm b/src/gacela_misc.scm
index b75a44e..d486b26 100644
--- a/src/gacela_misc.scm
+++ b/src/gacela_misc.scm
@@ -20,3 +20,7 @@
     (cond ((> (* p 2) n) p)
 	  (else (power (* p 2) n))))
   (power 1 n))
+
+(define-macro (pushnew elem list)
+  `(cond ((not (find (lambda (e) (eq? e ,elem)) ,list))
+	  (set! ,list (cons ,elem ,list)))))