[racket] reader.html: documentation for complex number reading

From: Tim Brown (tim.brown at timb.net)
Date: Fri Mar 29 16:24:17 EDT 2013


On 29 Mar 2013 03:03, "Matthew Flatt" <mflatt at cs.utah.edu> wrote:
> FWIW, there are number-parsing regexp constructions in
>  collects/r6rs/private/readtable.rkt (see `rx:number')
> [...]
> The first, as the path suggests, is R6RS instead of Racket.

I've just looked at the R6RS regexps. Thanks for the pointers, but... they
(it?) have been broken down into sensible sized chunks; but I'm sure that
once you've built up a single string (the kind that grep would like) you'll
end up with a three-page monstrosity like mine.

For amusement, here is the head of VIM's scheme.vim syntax file:

" Vim syntax file
> " Language:    Scheme (R5RS + some R6RS extras)
> " Last Change:    2009 Nov 27
> " Maintainer:    Sergey Khorev <sergey.khorev at gmail.com>
> " Original author:    Dirk van Deun <dirk at igwe.vub.ac.be>
> " This script incorrectly recognizes some junk input as numerals:
> " parsing the complete system of Scheme numerals using the pattern
> " language is practically impossible: I did a lax approximation.

Schemes' number representations are notorious!

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