Hi graff,

thanks for your efforts. As it happens I'm particularly interested in the part about which you wrote that you cannot explain it either (optional grouping not captured).

As a workaround I've written to regexes coupled with if: 
my $re1 = qr/beer=(\d{2}).*chips=(\d{3})/;
my $re2 = qr/vodka=(\d{2})/;

if ( $str =~ /$re1 ) {
  my $m1 = $1;
  my $m2 = $2;
  if ( $str =~ /$re2/ ) {
    #use that capture and go on...
  }
}

[download]


This does exactly what I want it to do; it's just that I'd like to learn if it's possible to achieve with a single regex. And if not, then why?

While reading up and googling this I realized that I basically do not understand much about greedy/non-greedy quantifier and/or optional groups.

For example I am also puzzled why 
"cat:dog" =~ /(cat)*/;

[download]
captures "cat", but 
"dog:cat" =~ /(cat)*/;

[download]
doesn't.

Cheers

In reply to Re^4: Likely trivial regex question by moodywoody
in thread Likely trivial regex question by moodywoody

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