[darcs-devel] user experience engineering note

Don Stewart dons at galois.com
Mon Jan 14 19:50:12 UTC 2008


nicolas.pouillard:
> Excerpts from Alexander Staubo's message of Mon Jan 14 19:24:49 +0100 2008:
> > On 1/14/08, zooko <zooko at zooko.com> wrote:
> > > So this is a good example of how the problems of user experience are
> > > sometimes different (and "simpler") than the problems of engineering
> > > the actual core algorithms of your program.  "Responsiveness" is, I
> > > think, the most important single factor in user interaction design.
> > 
> > I agree.
> 
> I agree too.
> 
> I'm sure that we loose many people due to darcs responsiveness.
> 
> In  fact, there is few darcs commands, but they are very powerful, perhaps too
> much  powerful  sometimes.  Darcs  accept to start operations that are way too
> long  to  complete.  The user can be easily frustrated because he doesn't know
> if the command will run forever or complete the next second.
> 
> I  concede  that  using  lazy  functional  programming  makes progression more
> difficult  than  usual.  It's in fact more challenging but we want to keep the
> core code clear and unobstructed.

It's not Haskell per se, or laziness, that's the cause of darcs lack of
responsiveness -- GHC produces highly optimised native code, certainly
much much faster than say, Python.

Slow algorithms are the issue here.

-- Don


More information about the darcs-devel mailing list