[tpm] New Regex question
uri at stemsystems.com
Sat Oct 27 20:56:12 PDT 2012
On 10/27/2012 08:52 PM, Rob Janes wrote:
> sounds a bit muddy ...
> just to clarify, what I found to my surprise, is that
> $exp =~ s/(\s)$1+/$1/g;
> replaces mixed strings of white space with the first character. leading me
> to conclude that the first $1 actually is the \s, not the specific
> character matched. However, in the second part of the s, the $1 did indeed
> give the white space. So the $1 in the context of searching appears to
> render as the regex, not the characters matched. While in the context of
> replacing, the $1 renders as the actual characters matched, not the regex
> hope that makes it clearer.
sorry but no.
$1 in the regex is what $1 was BEFORE the regex. it gets interpolated
and then parsed as a regex. it is not related to the () in the regex.
only \1 will be the grabbed text from that (). and $1 in the replacement
is just the string matched in the () which is any single whitespace char.
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