@hackage bitvec1.0.0.0

Bit vectors library for Haskell.

The current vector package represents unboxed arrays of Bool allocating one byte per boolean, which might be considered wasteful. This library provides a newtype wrapper Data.Bit.Bit and a custom instance of unboxed Data.Vector.Unboxed.Vector, which packs booleans densely. It is a time-memory tradeoff: 8x less memory footprint at the price of moderate performance penalty (mostly, for random writes).

Thread safety

• Data.Bit is faster, but thread-unsafe. This is because naive updates are not atomic operations: read the whole word from memory, modify a bit, write the whole word back.

• Data.Bit.ThreadSafe is slower (up to 2x), but thread-safe.

Similar packages

• bv and bv-little offer only immutable size-polymorphic bit vectors. bitvec provides an interface to mutable vectors as well.

• array is memory-efficient for Bool, but lacks a handy Vector interface and is not thread-safe.