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Re: SRFI-115 issues



On Tue, Oct 22, 2013 at 10:40 PM, John Cowan <cowan@xxxxxxxxxxxxxxxx> wrote:
Alex Shinn scripsit:

> I actually need to separate the features better because things like
> "non-greedy" repetitions can actually be supported by non-backtracking
> implementations, "if" is just a shortcut for "or" with a look-ahead,
> and I have to think about whether it's possible for atomic/commit to
> be supported without backtracking.
>
> Ultimately with a little effort everything can be supported.  One
> trick to support backreferences in DFA impls is to replace them with
> .* and use post-processing to verify.  So it's more a matter of what's
> readily available, not what's possible.

In that case I think there should be a unified system and the feature
mechanism should be abandoned.

You didn't give any justification for this conclusion.
What's wrong with providing features?

-- 
Alex