[darcs-devel] darcs patch: (Re)upgrade createPS and generatePS to D... (and 8 more)

[Don Stewart]

droundy:
> On Wed, Feb 06, 2008 at 11:44:42AM -0500, David Roundy wrote:
> > > Maybe we can egg on the bytestring people and get them to submit
> > > patches taking this further down (for example, they could improve our
> > > between newlines and nth newline stuff).
> > 
> > That'd be nice.
> 
> I should note, though, that we can also make probably faster progress by
> simply reducing the dependency on the counting of lines.  In particular,
> I'd like to change Hunk to store a new and old PackedString + line number
> counts, rather than storing new and old [PackedString].  We'd still need to
> find the nth newline, etc, but we'd use much less memory and probably be
> faster to boot.  Even better when we introduce (maybe before darcs 2 is
> released?) a new hunk file format that doesn't have all those +'s and -'s.
> Then parsing is lightning fast and we won't need duplicate copies of the
> hunk data in memory.

I wonder if Data.Sequence would help here. Indexing is much cheaper. (Yi
is  using this to index the nth line of a buffer cheaply).