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Any one further investigation, it seems that my original solution suffered from a fundamental problem.

my %hash = (one => 1, two => 2, three => 3); my @keys = qw(four five six); my @slice = @hash{@keys};

@slice is now contains four undef elements, where I thought it would be an empty list (don't know why I thought that - it was very early in the morning.

If the hash slice was interpreted as an array, it would therefore always be true and therefore doesn't solve ChOas' original problem. That would be better addressed using something like:

if (grep { exists %hash{$_} } @keys) { print "yep\n"; } else { print "nope\n"; }
--
<http://www.dave.org.uk>

"Perl makes the fun jobs fun
and the boring jobs bearable" - me


In reply to Re: Re: Re: Hash slices ? by davorg
in thread Hash slices ? by ChOas

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