fix build script and add pragma

build.sh

 #!/bin/sh
 cd profile
-rm profile.tar
+rm -f profile.tar
 tar -cvf profile.tar *
 cd ..
-cabal install --force-reinstalls || return 1
+cabal install --force-reinstalls || exit 1
 cd ihaskell-display
 for dir in `ls`
 do
     cd $dir
-    cabal install || return 1
+    cabal install || exit 1
     cd ..
 done
 

src/IHaskell/Eval/Completion.hs

-{-# LANGUAGE NoImplicitPrelude, OverloadedStrings #-}
+{-# LANGUAGE NoImplicitPrelude, OverloadedStrings, DoAndIfThenElse #-}
 {- |
 Description : Generates tab completion options.
 
@@ -192,4 +192,4 @@ completePath currDir exts prefix
           cut (x:xs) z@(y:ys) | x == y = cut xs ys
                               | otherwise = z
           cut _ z = z 
-      in relativeCompletions
+      in relativeCompletions
\ No newline at end of file