On 6/13/07, James <[EMAIL PROTECTED]> wrote:
Thanks all, I have something working
> $data =~ s/(.*\n)(?=\1)//g;
Can anyone explain the (?=\1) bit? I get the search replace.
J.
Didn't understand it myself, but see:
http://www.boost.org/libs/regex/doc/syntax_perl.html
Search for Back references
And look at Perl Extended Patterns -> Lookahead
"(?=pattern) consumes zero characters, only if pattern matches."
So... It searches for .*\n and replaces it with "" if there is another
instance of same pattern right after this one.
ie replaces .*\n with "" if it is immediately repeated.
Cool!
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