From: simonmar <unknown>
Date: Mon, 14 Mar 2005 15:52:03 +0000 (+0000)
Subject: [project @ 2005-03-14 15:52:03 by simonmar]
X-Git-Tag: arity-anal-branch-point~31
X-Git-Url: http://git.megacz.com/?p=ghc-base.git;a=commitdiff_plain;h=f0f966ee96e24226c5a68bf1ad3c87bb1bd6c8ee

[project @ 2005-03-14 15:52:03 by simonmar]
doc comparing
---

diff --git a/Data/Ord.hs b/Data/Ord.hs
index 2be636c..b2f00f9 100644
--- a/Data/Ord.hs
+++ b/Data/Ord.hs
@@ -23,5 +23,12 @@ module Data.Ord (
 import GHC.Base
 #endif
 
+-- | 
+-- > comparing p x y = compare (p x) (p y)
+--
+-- Useful combinator for use in conjunction with the @xxxBy@ family
+-- of functions from "Data.List", for example:
+--
+-- >   ... sortBy (comparing fst) ...
 comparing :: (Ord a) => (b -> a) -> b -> b -> Ordering
 comparing p x y = compare (p x) (p y)