#7860: Add more bit fiddling functions to 'integer-gmp' --------------------------------+------------------------------------------- Reporter: lebedev | Owner: Type: feature request | Status: new Priority: normal | Milestone: Component: libraries (other) | Version: 7.6.3 Resolution: | Keywords: gmp Os: Unknown/Multiple | Architecture: Unknown/Multiple Failure: None/Unknown | Difficulty: Unknown Testcase: | Blockedby: Blocking: | Related: #3489 --------------------------------+------------------------------------------- Comment(by lebedev): Well, it looks like it's always safe to clear bit in a small-ish integer using operations on Int# and Word#: {{{ clearBitInteger :: Integer -> Int# -> Integer clearBitInteger (S# j) i = -- We can always safely celear a bit of a _small_ integer. let !mask = int2Word# (1# `iShiftL#` i) `xor#` int2Word# (negateInt# 1#) in S# (word2Int# (int2Word# j `and#` mask)) clearBitInteger (J# s d) i = let !(# s', d' #) = clearBitInteger# s d i in J# s' d' }}} What do you think? I can modify {{{setBitInteger}}} in a similar way. -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7860#comment:7 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler