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Re: Simple way to split on last match?

by Marshall (Prior)
on Aug 05, 2012 at 19:22 UTC ( #985567=note: print w/ replies, xml ) Need Help??


in reply to Simple way to split on last match?

In Perl, you can use the index of [-1] to indicate the last array element. A REGEX would work fine here also. I don't know without benchmarking, but I suspect that the regex version is actually faster.

#!/usr/bin/perl -w use strict; my $line ='last -- From --00--SPLIT ?--11452'; my ($last) = (split(/--/, $line))[-1]; print "using split: $last\n"; ($last) = $line =~ /(\d+)\s*$/; print "using regex: $last\n"; __END__ Prints: using split: 11452 using regex: 11452
Update: I guess I should say that the parens around ($last) are necessary to put $last into a list context, otherwise you just get 1 or 0 value. Here we want the actual value that was captured rather than whether it the expression "worked" or "not.


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Re^2: Simple way to split on last match?
by aturtle (Novice) on Aug 05, 2012 at 20:36 UTC
    Hey thanks! my ($last) = (split(/--/, $line))-1; Works The -1 is what is significant in getting the last one i guess. -Turtle
      Yes that is correct.
      A Perl "list slice" can have indices of [-3,2,-1,3,-4] in any order. The one thing that I wish Perl could do that it cannot do: is to say "I want all of the stuff past index X" in a simple syntax.

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