Re: ELisp: special read syntax for regular expressions?

[Joost Diepenmaat]

Ilya Zakharevich <nospam-abuse@ilyaz.org> writes:

> [A complimentary Cc of this posting was sent to
> David Hansen 
> <david.hansen@gmx.net>], who wrote in article 
> <mailman.10052.1207428807.18990.help-gnu-emacs@gnu.org>:
>> Have a look at the Gauche Scheme implementation.  It has a regexp read
>> syntax: #/.../.
>
> IMO, having SLASH hardwired as a delimiter is a silly choice; it makes
> matching a slash harder, UNNECESSARILY.  If one MUST hardwire some
> delimiters, it should better be () (since un-backwacked parens are
> almost guarantied to be matched inside a regular expression, one needs
> no extra backwacking to enclose the REx into MATCHED parens).

Agreed. From using loads of regexes in perl, I much prefer to use qr(
.. ) or qr{ ... }. Or at least, forward slashes in matches are just much
too common in many typical matches (URLs & paths, for instance). But you
would know that :-)

> Any thoughts?  Is /(REX) prohibited by some considerations?

Dunno. I'd think that #{ ... } or #( ... ) or possibly even #r{ .. } or
#r( .. ) would be clearer as "special reader syntax". But I really don't
know enough about (emacs) lisp reader constructs.

> P.S.  I just released v6.2 of CPerl mode; now it has a menu entry
>       Perl/Micro-docs/Show-Faces which inserts an example Perl code
>       with (all?) possible faces shown (when proper facification is
>       enabled).  This may simplify the part of this thread concerned
>       with REx facification in CPerl.
>
>       See ilyaz.org/software/emacs

That link doesn't seem to exist; it redirects to
http://www.yeah.com/software/emacs

Cheers,
Joost.

-- 
Joost Diepenmaat | blog: http://joost.zeekat.nl/ | work: http://zeekat.nl/