expand test

resources/scm/scheme/base.scm

@@ -1,3 +1,9 @@
 (define-library (scheme base)
-  (export lambda)
-  (import (scheme primitives)))
+  (export lambda begin define define-syntax
+          syntax-rules if when)
+  (import (primitives+builtins))
+  (begin
+    (define-syntax when
+      (syntax-rules ()
+        ((_ test body)
+         (if test (begin body)))))))