bytestring-lexing-0.5.0.5: Efficiently parse and produce common integral and fractional numbers.
The bytestring-lexing package offers extremely efficient
parsers for some common lexemes: namely integral and fractional
numbers. In addition, it provides efficient serializers for (some
of) the formats it parses.
As of version 0.3.0, bytestring-lexing offers the best-in-show parsers for integral values. (According to the Warp web server's benchmark of parsing the Content-Length field of HTTP headers.) And as of version 0.5.0 it offers (to my knowledge) the best-in-show parser for fractional/floating numbers.
Some benchmarks for this package can be found at: http://code.haskell.org/~wren/bytestring-lexing/bench/html