in reply to Quick regex

Like this? 

$s = 'fred_bill_john_jack_joe_mary_eugene';;

$s =~ /(^[^_]+_[^_]+_[^_]+_)/ and print "'$1'";;

'fred_bill_john_'

[download]

Or this? 

$s =~ /(^(?:[^_]+_){3})/ and print "'$1'";;

'fred_bill_john_'

[download]
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Re^2: Quick regex
by Karger78 (Beadle) on Nov 24, 2009 at 17:34 UTC
    that looks good, but how do i kill the trailing _ So your example would look like this 'fred_bill_john'
[reply]

      You want to match 

      name, dash, name, dash, name

      [download]

      or 

      ( name, dash ) x 2, name

      [download]

      so 

      my ($substr) = $s =~ /^((?:[^_]*_){2}[^_]*)/
    or die("No match\n");

      [download]
[reply]
[d/l]
[select]
      Everything in ( ) goes into $1, so move the last _ outside of )
[reply]
[d/l]

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