Poll of the week: How should std.regex handle unknown escape

[Vladimir Panteleev]

On Sat, 03 Dec 2011 17:51:13 +0200, Dmitry Olshansky  
<dmitry.olsh at gmail.com> wrote:

> treat every \<something> as plain <something> (ignoring \) inside  
> character classes [] if it's not a known escape sequence like \w, \d,  
> \uXXXX, \W, \cA -\cZ and so on.

I think the common intuitive rules regarding escapes in regexes are as  
follows:

1) Unescaped punctuation usually has special meaning (so people often  
escape all punctuation literals)
2) Unescaped letters are literal
3) Escaped punctuation is literal
4) Escaped letters have special meaning

Therefore, I think that std.regex should throw on unrecognized *letter*  
escapes. It's very likely that the user might be trying to use a character  
class or feature from another regex engine, but unsupported by std.regex.

-- 
Best regards,
  Vladimir                            mailto:vladimir at thecybershadow.net