[Haskell-cafe] Interesting new user perspective

[Jonathan Cast]

On Fri, 2008-10-10 at 15:00 -0500, Tommy M. McGuire wrote:
> On 10 Oct 2008, at 7:05 pm, Jonathan Cast wrote:
>  > Parsec makes recursive descent parsers as easy to use in Haskell as
>  > regexps are in Perl.  No reason not to expose newcomers to Haskell to
>  > the thing it does best.
> 
> Is it wrong to use Parsec to parse regular expressions for a really 
> simple regex engine[4]?

That looks about right.  And, as you point out, it's easier to
understand than a direct parser.  I would also re-code the engine itself
in Parsec, though (probably using a finite state machine implementation,
which (I think; I haven't tried it yet) would end up looking rather like
a manual unfolding along the lines of Koen Claessen's parallel parsing
process [1]).

jcc

[1] http://www.cs.chalmers.se/~koen/Papers/parsing-pearl.ps