If as both your words and code imply, you are only after xxx and xxx always has length 3 then:

print substr($var,0,3);

is much simpler and faster than any regex.

If the length of xxx can vary then 

print substr($var, 0, index($var, ':'));

[download]

is almost as simple and still more efficient that a regex. (And easier to get right first time:)

If you actually want to get xxx, yyy, and zzz and they are always length 3, then 

my $p=0; print substr( $var, ($p=index($var, ':', $p+1 ))-3,3),$/ whil
+e $p > -1

[download]

will won't quite (see below for reason and below that for correction. do the trick. Though it is a little harder to get right first time.

The use of a regex only really comes into its own when the number, and length of the entities to be matched can both vary is a lot more efficient for even the simple cases than I thought!

Cor! Like yer ring! ... HALO dammit! ... 'Ave it yer way! Hal-lo, Mister la-de-da. ... Like yer ring!

In reply to Re: split question by BrowserUk
in thread split question by Anonymous Monk

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