Re: Regular expressions mystery

It 'worked' for me. You might want to let us know what you are trying to capture or accomplish and show a complete program.

use warnings;
use strict;

foreach my $str ( 'LLLLLLLLLLLLLLLLLLLOOOOOOOOOOOOO', 'LLLLLLLLLLCOOOO
+OOOOOOOOOOOOOOOOOO' ){
    if($str=~/^(L+)/ or $str=~/^(L+C)/) {
        print "matched '$1'\n";
    }
}
__END__
matched 'LLLLLLLLLLLLLLLLLLL'
matched 'LLLLLLLLLL'
[download]

Comment on Re: Regular expressions mystery Download Code

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Re^2: Regular expressions mystery by AnomalousMonk (Archbishop) on Jul 01, 2018 at 13:28 UTC
`AnonyMonk`: Note that you will never capture the `C` character in the string (if this is what you want to do) because the `$str =~ /^(L+)/` expression will always match first in `if ($str =~ /^(L+)/ or $str =~ /^(L+C)/) { ... }` for the strings you give as examples. If you want the `C` captured, reverse the order of the matches `if ($str =~ /^(L+C)/ or $str =~ /^(L+)/) { ... }` or much better yet IMHO, just use a single regex with an optional `C` match `if ($str =~ /^(L+C?)/) { ... }` (See the `?` quantifier in perlre.) Give a man a fish: `<%-{-{-{-<`	[reply] [d/l] [select]
Re^3: Regular expressions mystery by Anonymous Monk on Jul 01, 2018 at 17:01 UTC
Thank you very much! Good point	[reply]