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Re: [Scheme-reports] Scheme r7rs syntax described by ABNF
I added the following TODO item to my local copy and also added one new item as a placeholder.
;;; - Fix definition of peculiar-identifier and
;;; pattern-peculiar-identifier not to include "+i", "-i", and
;;; - Review definitions to check if syntactically correct but
;;; semantically incorrect numbers can be avoided (e.g. "#e0/0",
;;; "#e+1/0", "#e-1/0", "#e"<infnan>).
I couldn't find any description for such issues in the r7rs draft (but maybe I need to look closer ?).
Or is it common practice to leave such items as rationals?
On Jan 17, 2013, at 12:07 , Joseph Wayne Norton <norton@x> wrote:
> Alex -
> Without this extended syntax, the spec becomes more tedious (and error prone).
> I'm aware of two ABNF parser libraries that support this extended syntax:
> abnfgen - http://www.quut.com/abnfgen/
> abnfc - https://github.com/ubf/abnfc/tree/norton-upstream%2Bgenerators
> I tested this draft of r7rs with the abnfc tool.
> I'll add a TODO list at the top of this draft for the +i and +nan.0 symbols.
> Joe N.
> On Jan 17, 2013, at 11:33 AM, Alex Shinn <alexshinn@x> wrote:
>> On Wed, Jan 16, 2013 at 11:24 PM, ノートン ジョーセフ ウェイ ン <norton@x> wrote:
>> Hello again.
>> I have an updated draft for the formal syntax of Scheme r7rs written in ABNF. This draft is based on updates since r7rs-draft-8.pdf and includes all sections except for quasiquotations. The datum and expression sections have undergone some quickcheck-style unit testing. I'd appreciate any review and feedback.
>> Thanks for doing this. The big advantage of the RFC format is
>> that it's machine readable - have you tried running this through
>> any ABNF parser libraries?
>> To use it practically you'd need to tie up some of the loose ends,
>> e.g. +i and +nan.0 should not parse as symbols. This is possible
>> but a little tedious to spec out.
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