Made bits-extras dependency optional.

1 files changed, 10 insertions, 4 deletions

diff --git a/bittorrent.cabal b/bittorrent.cabal
index efc1cb0d..a09d4530 100644
--- a/bittorrent.cabal
+++ b/bittorrent.cabal
@@ -46,6 +46,10 @@ flag network-uri
   description:         Use network-uri package.
   default:             True
 
+flag bits-extras
+  description:         Use more-effecient bits-extras bitwise operations.
+  default:             False
+
 library
   default-language:    Haskell2010
   default-extensions:  PatternGuards
@@ -97,9 +101,7 @@ library
                        System.Torrent.FileMap
                        System.Torrent.Tree
 
-  build-depends:       base       == 4.*
-                     , lifted-base
-                     , bits-extras  >= 0.1.2
+  build-depends:       lifted-base
                      , convertible  >= 1.0
                      , pretty       >= 1.1
 
@@ -171,12 +173,16 @@ library
                      , directory   >= 1.2
                      , filepath    >= 1.3
                      , mmap        >= 0.5
-
   if flag(network-uri)
     Build-depends:     network      >= 2.6
                      , network-uri  >= 2.6
   else
     Build-depends:     network      >= 2.4 && < 2.6
+  if flag(bits-extras)
+    build-depends:     base       == 4.*
+                     , bits-extras  >= 0.1.2
+  else
+    build-depends:     base       >= 4.8
 
   ghc-options:         -Wall
   ghc-prof-options: