Lazy -containers +bytestring
A time and space-efficient implementation of lazy byte vectors using lists of packed Word8 arrays, suitable for high performance use, both in terms of large data quantities, or high speed requirements. Byte vectors are encoded as lazy lists of strict Word8 arrays of bytes. They provide a means to manipulate large byte vectors without requiring the entire vector be resident in memory.
Some operations, such as concat, append, reverse and cons, have better complexity than their Data.ByteString equivalents, due to optimisations resulting from the list spine structure. And for other operations lazy ByteStrings are usually within a few percent of strict ones, but with better heap usage. For data larger than the available memory, or if you have tight memory constraints, this module will be the only option. The default chunk size is 64k, which should be good in most circumstances. For people with large L2 caches, you may want to increase this to fit your cache.
This module is intended to be imported qualified, to avoid name clashes with Prelude functions. eg.
> import qualified Data.ByteString.Lazy as B
Original GHC implementation by Bryan O'Sullivan. Rewritten to use UArray by Simon Marlow. Rewritten to support slices and use ForeignPtr by David Roundy. Polished and extended by Don Stewart. Lazy variant by Duncan Coutts and Don Stewart.