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in reply to Slice a hash to get a subset hash.

What I usually do is something like this (your final solution in the OP):

my %location = map { $_ => $london{$_} } qw(Long Lat Elevation);

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However, if that isn't clean enough for you, you could use prototypes to create a bit of syntactic sugar:

sub extract(\%@) {
  my $h = shift;
  map { $_ => $h->{$_} } @_;
}

# usage
my %location = extract %london, qw(Long Lat Elevation);
my %stats = extract %london, 'Population', 'Area'

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Re^2: Slice a hash to get a subset hash.
by chrestomanci (Priest) on Feb 24, 2011 at 14:41 UTC

    Thank you, that is a nice bit of syntactic sugar. I would add it to my toolbox, but I suspect that if I did I would be for ever explaining it to the other perl programers at $work.

    I think I will stick with the map method that I put in the original post. It is good enough.

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