Changes between Version 3 and Version 4 of ViewPatterns

Timestamp:

01/24/07 09:46:32 (6 years ago)

Author:

simonpj

Comment:

--

ViewPatterns

@@ -320 +320 @@
   f (snoc | x xs) = ..          -- Use "|" instead of "->"
   g (bits 3 | b bs) = ...
-
+}}}
+Another possibility is to use a backward arrow, more like pattern guards:
+{{{
   f ((x,xs) <- snoc) = ...  -- More like pattern guards
+}}}
+But that messes up the left-to-right flow that is useful in some cases.
+For example, compare these:
+{{{
+  parsePacket1 (bits 3 -> n (bits n -> val bs)) = ...
+
+  parsePacket2 (n (val bs <- bits n) <- bits 3) = ...
 }}}