From 3a2182326cea438b339d72fd08fb076fce42328f Mon Sep 17 00:00:00 2001
From: Neil Brown <neil@twistedsquare.com>
Date: Tue, 14 Apr 2009 16:58:38 +0000
Subject: [PATCH] Added a new function in Utils for splitting a file into its
 extension, and the rest of it

---
 common/Utils.hs | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/common/Utils.hs b/common/Utils.hs
index 632af8d..1ac65dc 100644
--- a/common/Utils.hs
+++ b/common/Utils.hs
@@ -58,6 +58,14 @@ joinPath base new
         "." -> new
         dir -> dir ++ new
 
+-- | Splits a file into its stem (whole path minus extension) and its extension
+-- (without the dot):
+splitExtension :: String -> (String, String)
+splitExtension s
+  = case span (/= '.') (reverse s) of
+      (whole, []) -> (s, []) -- no extension
+      (revExt, _ : revRest) -> (reverse revRest, reverse revExt)
+
 -- | Given a monadic action wrapped in a `Maybe`, run it if there's one there;
 -- if it's `Nothing`, then do nothing.
 doMaybe :: Monad m => Maybe (m ()) -> m ()