I tend to do:

my %h2; /^cat/ and $h2{ $_ } = $h1{ $_ } for keys %h1;

[download]

Which might be seen as "cheating" as a one-liner; but it is often difficult to put the initialisation of a hash inline.

It is also quite more efficient than map and/or grep for larger hashes, by avoiding the creation of intermediate lists.

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re: Is there a simple syntax to logically slice a hash? by BrowserUk
in thread Is there a simple syntax to logically slice a hash? by misterperl

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