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Re: regexp and valid-sre?

This page is part of the web mail archives of SRFI 115 from before July 7th, 2015. The new archives for SRFI 115 contain all messages, not just those from before July 7th, 2015.

On Tue, Nov 26, 2013 at 11:17:41AM -0800, Michael Montague wrote:
> The only use case for 'valid-sre?' mentioned so far is Peter's 
> interactive regular expression IDE. The C standard does not require the 
> -fsyntax-only option. These do not seem like compelling arguments for 
> including 'valid-sre?'.

Like I said, it's the primitive operation.  When all you want is
to check validity, compiling and handling an exception is very
inelegant and feels like jumping through unnecessary hoops.
It makes sense to provide the more primitive operations where
there's a chance someone might want to use those.

I haven't seen any particularly compelling arguments against
including it, either.  It's just a straightforward predicate,
and you can always implement it the way you indicate: try to
compile and return #t, and upon catching an exception return #f.