Explain the use of the token in try-rules.

axch · May 23, 2013 · 41d2d56 · 41d2d56
1 parent b3998a4
commit 41d2d56
Showing 1 changed file with 1 addition and 0 deletions.
diff --git a/pattern-dispatch.scm b/pattern-dispatch.scm
@@ -42,6 +42,7 @@
       (if (null? rules)
           (fail)
           (let ((answer ((car rules) data token)))
+            ;; Distinguish failure from idempotent success
             (if (eq? answer token)
                 (per-rule (cdr rules))
                 answer))))))