[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

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

From: Michael Heerdegen
Subject: Re: Make peg.el a built-in library?
Date: Sat, 09 Oct 2021 03:31:03 +0200
User-agent: Gnus/5.13 (Gnus v5.13) Emacs/29.0.50 (gnu/linux)

Eric Abrahamsen <eric@ericabrahamsen.net> writes:

> Hi all,
> In my on-again-off-again quest to not have to write text parsers myself,
> I was pointed towards the PEG library (in ELPA), which does pretty much
> exactly what I want (Parsing Expression Grammars).

I like the idea, and I have some remarks:

(1) Can we improve the introduction in the file header a bit?  I would
add a link to the wikipedia page:


it explains some background.

And: one example could contain the (non-standard if you only know
regexps, but very educative) solution to the problem: "how do you jump
over arbitrary text preceding a match?" (the answer seems to be: "use
`or' and recursion", at least this is what I found out by myself after a

(2) Would (replace E RPL) not be much more useful if it would be allowed
to pop from the stack?  Something like (replace E [VAR...] -- REPL)
where REPL could use the VAR bindings?  Background is of course that a
replacement may depend on intermediate parsing results.

(3) `(_ --) seems to produce an "Empty let body" compiler warning - can
we silence it?

(4) How hard would it be to parse regexps (or translate  `rx' forms) into
an equivalent peg?

(5) We need to add a Game-like tutorial to PEGs called Peg-Man.  Ok,
that one was only a joke.




reply via email to

[Prev in Thread] Current Thread [Next in Thread]