| Copyright | (c) Edward Kmett 2013-2014 |
|---|---|
| License | BSD3 |
| Maintainer | Edward Kmett <[email protected]> |
| Stability | experimental |
| Portability | non-portable |
| Safe Haskell | Trustworthy |
| Language | Haskell98 |
Data.Bits.Extras
Description
Calculate a number of fiddly bit operations using fast de Bruijn multiplication tables.
- class (Num t, FiniteBits t) => Ranked t where
- log2 :: Word32 -> Int
- msb :: Ranked t => t -> Int
- w8 :: Integral a => a -> Word8
- w16 :: Integral a => a -> Word16
- w32 :: Integral a => a -> Word32
- w64 :: Integral a => a -> Word64
- assignBit :: Bits b => b -> Int -> Bool -> b
- zeroBits :: Bits a => a
- oneBits :: Bits b => b
- srl :: Bits b => b -> Int -> b
Documentation
class (Num t, FiniteBits t) => Ranked t where Source #
Minimal complete definition
Methods
Calculate the least significant set bit using a debruijn multiplication table. NB: The result of this function is undefined when given 0.
Calculate the number of trailing 0 bits.
Calculate the number of leading zeros.
zeroBits is the value with all bits unset.
The following laws ought to hold (for all valid bit indices n):
clearBitzeroBitsn ==zeroBitssetBitzeroBitsn ==bitntestBitzeroBitsn == FalsepopCountzeroBits== 0
This method uses clearBit (bit 0) 0zeroBits for
types which possess a 0th bit).
Since: 4.7.0.0