Efficiency improvement to last change.

diff --git a/v7/src/sf/subst.scm b/v7/src/sf/subst.scm
index c0f3f949df2f5d57775da1b2f093779c445b7f24..724c2e7638e62f4d26b2cfd3212ad9dac31223ae 100644 (file)
--- a/v7/src/sf/subst.scm
+++ b/v7/src/sf/subst.scm
@@ -1,6 +1,6 @@
 #| -*-Scheme-*-
 
-$Header: /Users/cph/tmp/foo/mit-scheme/mit-scheme/v7/src/sf/subst.scm,v 4.3 1988/09/22 18:42:57 jrm Exp $
+$Header: /Users/cph/tmp/foo/mit-scheme/mit-scheme/v7/src/sf/subst.scm,v 4.4 1988/11/05 22:14:02 cph Rel $
 
 Copyright (c) 1988 Massachusetts Institute of Technology
 
@@ -828,12 +828,11 @@ forms are simply removed.
           (constant/make (apply (constant/value operator)
                                 (map foldable-constant-value operands))))
 
-         ;; (force (delay x)) ==> x
-         ((and (constant? operator)
-               (primitive-procedure? (constant/value operator))
-               (eq? (constant/value operator) 
-                    (make-primitive-procedure 'FORCE))
-               (eq? (length operands) 1)
+         (
+          ;; (force (delay x)) ==> x
+          (and (constant? operator)
+               (eq? (constant/value operator) force)
+               (= (length operands) 1)
                (delay? (car operands)))
           (delay/expression (car operands)))