First, you're missing a ~ character. It should be: -- Not necessary. There's an implicit match against $_.--geb

(code deleted)

Second, let's break it down: 

my ($label) =~ /      # begin 
                  \.    # find a literal . 
                  (      # start capturing
                   [^\.] # Any character that isn't a \ or .
                   *    # zero or more
                   )      # stop capturing
                  $      # only match from the end of the string
                   /       # end;

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In a nutshell this will match the "extension" of the data you provided, i.e. the "five" in "one.five" or the "12" in "two.ten.12". What's matched is captured into $label.

There's lots of info on regexes both here and in the regular Perl documentation. They can be challenging at first, but are well worth the effort to figure out. :-D

Gary Blackburn
Trained Killer

Edited

In reply to Re: About regular expression by Trimbach
in thread About regular expression by benlaw

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