On Mon, Mar 11, 2013 at 4:45 PM, Simon Peyton-Jones <simonpj@microsoft.com> wrote:
B Better for internal implementation (eg using containers or bytestring in base)

Note that this also means better code for external clients, as we can offer e.g. a better System.IO that lets people use Handles to read Text and ByteStrings in a more natural way (i.e. the I/O functions will be in one place, not spread out throughout N data structure libraries).