Re: [Chicken-users] Regex help.

[Peter Bex]

On Sat, Mar 01, 2008 at 04:21:16AM -0700, Matthew Welland wrote:
> What am I not getting here?
> 
> DB<1> "\\foo "=~m/^\\(.*) $/;print $1;
> foo
> 
> irb> "\\foo ".match(/^\\(.*)\s*$/);puts $1
> foo
> 
> csi> (string-match (regexp "^\\(.*)\\s*$") "\\foo ")
> #f

It tells me
Error: (regexp) cannot compile regular expression - unmatched parentheses

In chicken, you're doing the equivalent of Ruby's
"\\foo ".match(/^\(.*)\s*$/)

So, to get two backslashes in the string, use four of them;
one to escape the first, one to escape the second, resulting in
two backslashes which count for the regex as one escaped backslash.

#;2> (string-match (regexp "^\\\\(.*)\\s*$") "\\foo ")
("\\foo " "foo ")

HTH,
Peter
-- 
http://sjamaan.ath.cx
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