perl: slice of a hash vs hash slice

perl hash slices are a way to access several elements of a hash simultaneously using a list of subscripts. It's more convenient than writing out the individual elements as a list of separate scalar values.

I recently needed to create a slice of a hash rather than a hash slice, ie. I wanted to create a hash with a subset of the key/value pairs from another hash.

Here's how I did it:

my %orginal = (foo => 'something', bar => 42, baz => 'king'); my %subset = map {$_ => $original{$_}} qw(foo bar)); # %subset is now: ( foo => 'something', bar => 42 )

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Robin Bowes

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