re vs. sgmllib (was: Moving from Perl to Python)

[Brian Rogoff]

On Sun, 26 Sep 1999, Tim Peters wrote:

> [Jon Fernquest]
> > Since regular expressions are just a short-hand way of specifying
> > (practically only *some*) regular languages whereas finite state
> > machines can specify any regular language the next logical step
> > would be a set of finite state tools like those that Xerox sells
> > (for several thousands of dollars I might add).
> 
> Then I hope we can skip the next logical step and leapfrog illogically to a
> real parser <wink>.  Part of the problem here is that what people want to
> parse these days-- from programming language fragments to SGML --isn't
> regular.  That doesn't stop them from trying to do it with regexps, and
> input-sensitive bug-ridden code is the result.  Heck, most people find it a
> challenge to write a correct regexp to match a Python string -- or even a C
> /**/ comment.  Not that regular languages aren't useful, but I expect their
> appropriate non-trivial applications will always be a wizard art.

It might be interesting to add SNOBOL4 style patterns to Python then.
There was some work by SNOBOL's creators to add SNOBOL patterns to a
language with more conventional syntax (REBUS was the name I think) but it 
got dropped when all of the effort shifted to Icon. 

-- Brian