Hi finfan,

..Doesn't seem to work. #MO and # MO do not match. Tried the regex tester at http://www.internetofficer.com/seo-tool/regex-tester/ and it says "no match"..

I know the code posted by toolic worked, I wanted to find out why it wasn't working on the website you mentioned. Tried it out and it worked with the following result:

Regular Expression Test Results

Tested pattern: ^#\s*[a-z]+
Applied options:
the comparison was case-insensitive
 
String 1: #MO
Result : true
 
String 2: # MO
Result : true
 
String 3: #mo
Result : true
 
String 4: # mo
Result : true
 
String 5: # 555
Result : false
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"Doesn't seem to work. #MO and # MO do not match."

That sounds like you forgot the 'i' modifier at the end of "/^#\s*[a-z]+/i".

"Tried the regex tester at http://www.internetofficer.com/seo-tool/regex-tester/ and it says "no match""

That site clearly states "We use Perl-style regular expressions." (not Perl regular expressions). It also seems to have limited functionality: it has a checkbox for the 'i' modifier and nothing for any of the other modifiers (see /PATTERN/msixpodualgc in "perlop: Regexp Quote-Like Operators").

Why not try it in a real perl script. As ++toolic provided you with the complete code, it's a simple copy-paste operation.

Sure they do:

$ cat 1078855.pl
use warnings;
use strict;

while (<DATA>) {
    print if /^#\s*[a-z]+/i;
}

__DATA__
#MO
# MO
#mo
# mo
# 555
$ perl 1078855.pl 
#MO
# MO
#mo
# mo
$
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