Re: Make peg.el a built-in library?

[Michael Heerdegen]

Helmut Eller <eller.helmut@gmail.com> writes:

> On Sun, Oct 10 2021, Michael Heerdegen wrote:
>
> > Is it practically possible to transform a regexp into a really
> > equivalent PEG, or is it too difficult, or would the resulting PEG just
> > be too large or inefficient?
>
> The LPEG people wrote a paper[*] about this problem.

IIUC their answer to the ordered `or' operator problem is simply, at the
end, to apply the distributive law when performing the transcription.
So e.g.

(and (or "a" "aa") "b") doesn't match "aab" as a peg, but
(or (and "a" "b") (and "aa" "b")) does.

Michael.