Make second arg to scons-set! optional.

diff --git a/src/runtime/syntax-constructor.scm b/src/runtime/syntax-constructor.scm
index c118e15719f585cdb408653843ca441babd921f9..e706fd2d7e785e6716854aca88bd8dd52adadb62 100644 (file)
--- a/src/runtime/syntax-constructor.scm
+++ b/src/runtime/syntax-constructor.scm
@@ -138,12 +138,14 @@ USA.
    (lambda (close)
      (list (close 'quote-identifier) id))))
 
-(define (scons-set! name value)
+(define (scons-set! name #!optional value)
   (make-open-expr
    (lambda (close)
-     (list (close 'set!)
-          name
-          (close-part close value)))))
+     (if (default-object? value)
+        (list (close 'set!) name)
+        (list (close 'set!)
+              name
+              (close-part close value))))))
 
 (define (let-like keyword)
   (lambda (bindings . body-forms)