An alternative to moritz's solution, you could do this:

@{ $aref } = split(/\D+/,"1,2xxx4:17");
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It says "store the result of the split into the array referenced by $aref". If $aref is undefined or an ArrayRef already, this works, even with strict and warnings.

$ perl -w -Mstrict -MData::Dumper -e 'my $x; @{$x} = split /\s/, "the 
+one true"; print Dumper($x)'
$VAR1 = [
          'the',
          'one',
          'true'
        ];
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If $aref is a different kind of reference, then you will get a fatal "Not an ARRAY reference".

$ perl -w -Mstrict -MData::Dumper -e 'my $x = {}; @{$x} = split /\s/, 
+"the one true"; print Dumper($x)'
Not an ARRAY reference at -e line 1.
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