Hello again,
I was about to do this, and then I discovered that it wouldn't work,
because there are a few special case PEGs that don't make sense as
macros. Specifically, in the context of a PEG, we interpret strings as
matching themselves, and those can't be made into macros.
So I went ahead and
On Tue 29 Mar 2011 14:47, Noah Lavine writes:
>> (define-peg-matcher and cg-and)
>
> That's doable. But if we're going to choose what to do entirely based
> on the first element of the list, then we could also just not define
> peg-sexp-compile at all and make each of the code generation function
> This last is the best. What if we define a module that serves as a
> registry of PEG match behaviors, like `(ice-9 peg matchers)'. Then we
> define `define-peg-matcher' or something, so that we can:
>
> (define-peg-matcher and cg-and)
>
> where define-peg-matcher is
>
> (define-syntax define-pe
On Mon 28 Mar 2011 22:44, Noah Lavine writes:
> - say that string PEGs can only occur at the top level of a PEG
> expression. The peg module has never been released, so no one uses
> this feature now anyway.
> - instead of defining a new function peg-extended-compile, redefine
> peg-sexp-compil
A variant on the second option would be first defining
peg-string-compile to just throw an error, then redefining it later to
actually compile the string. That seems a little less hackish, at
least to me.
A fifth option would be to make peg-sexp-compile take an optional
argument FUN-RECUR that it
> I've been working on that. The attached two patches break the
> circularity. The code still isn't organized brilliantly, but after
> applying these I think we would only want pretty minor cleanups before
> merging PEG into the main branch.
Actually, forget this bit. I wrote it before I remembere
Hi,
> I think the solution is to confront the circularity directly. It exists
> because the PEG s-exp grammar also deals with the string grammar, which
> needs an already-build PEG parser.
>
> Let's break it instead into layers without cycles: removing the string
> grammar from the s-exp code gen
On Sun 06 Mar 2011 06:25, Noah Lavine writes:
> Attached is a series of patches I've made for the wip-mlucy branch. It
> splits the PEG code into several little modules which go in
> module/ice-9/peg/. The original peg source file becomes very little.
> At the end it finally loses its big eval-wh
Here's another patch, which in retrospect may be the most useful of
the series. It adds a section called "PEG Internals" to the manual,
and begins documenting how PEG actually works. This should make
hacking PEG a lot easier.
Noah
On Sun, Mar 6, 2011 at 12:25 AM, Noah Lavine wrote:
> Hello all,
