Enhanced the update special form. Now instead of returning void, it r…

…eturns the new value of the updated slot.
sthilaid · Oct 14, 2009 · c2be9fa · c2be9fa
1 parent 524039e
commit c2be9fa
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Showing 2 changed files with 8 additions and 6 deletions.
diff --git a/src/class_.scm b/src/class_.scm
@@ -178,10 +178,12 @@
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 
 (define-macro (update! obj class field f)
-  (let ((objval (gensym 'objval)))
-   `(let ((,objval ,obj))
-      (,(gen-setter-name class field) ,objval
-       (,f (,(gen-accessor-name class field) ,objval))))))
+  (let ((objval (gensym 'objval))
+        (newval (gensym 'newval)))
+   `(let* ((,objval ,obj)
+           (,newval (,f (,(gen-accessor-name class field) ,objval))))
+      (,(gen-setter-name class field) ,objval ,newval)
+      ,newval)))
 
 (define-macro (set-fields! obj class field-val-list)
   (let ((obj-ptr (gensym 'obj)))

diff --git a/tests/class-tests.scm b/tests/class-tests.scm
@@ -178,9 +178,9 @@
         'ok
         'no)))
 
-(define-test test-update! "" 'ok
+(define-test test-update! "2" 'ok
   (let ((obj (make-A 1)))
-    (update! obj A a (lambda (x) (+ x 1)))
+    (display (update! obj A a (lambda (x) (+ x 1))))
     (if (= (A-a obj) 2)
         'ok
         'no)))