in reply to Re: Global regex giving up too soon
in thread Global regex giving up too soon

Thanks for the demo. I better review all my uses of /g. Why does it bother me that there isn't a modifier that could replace the loop in these cases? Probably because I could use one, and because there are so many other shortcuts in Perl.
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Re: Global regex giving up too soon
by Abigail-II (Bishop) on Jan 20, 2004 at 12:22 UTC
    There is standard idiom for it: 
        1 while $str =~ s/PAT/REPL/;

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    Abigail
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      1 while $str =~ s/PAT/REPL/;

      Is the idiom supposed to contain the /g modifier? You didn't include it and I can't say I've ever seen 1 while s/foo/bar/, only 1 while s/foo/bar/g;. So tell me, should there be a /g there or am I in for a new lesson in the regex classroom?

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        There doesn't have to be a /g modifier. For some regex/string pairs, it doesn't matter whether there's a /g modifier. For others, it does.

        Abigail

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        my $str = join ' ', map {"$_-PAT"} 1 .. 10;
warn $str;
1 while $str =~ s/PAT/REPL/;
die $str;
__END__
1-PAT 2-PAT 3-PAT 4-PAT 5-PAT 6-PAT 7-PAT 8-PAT 9-PAT 10-PAT at - line
+ 2.
1-REPL 2-REPL 3-REPL 4-REPL 5-REPL 6-REPL 7-REPL 8-REPL 9-REPL 10-REPL
+ at - line 4.

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        An infinite loop with 1 while 
        my $str = 'A b and A and c and A';
warn $str;
$str =~ s/A/a/i for  1,2,3; 
die $str;
__END__
A b and A and c and A at - line 3.
a b and A and c and A at - line 5.

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      I'll have to figure out if I'd remember what that means or if I should check $&. I think I got it. Ugly though.
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