As long as you treat a hash as a list of pairs, you can pass hashes around just like lists.

If you're interested in how to do Functional Programming in Perl, I highly recommend Higher Order Perl, which nowadays even exists as a free, legal, complete downloadable ebook.

Perl supports anonymous functions and closures, which are indispensable once you start passing code as parameters. Perl does not really support typing. Depending on who and how you ask, Perl is typed from very weak to very strong. It has implicit type conversions and no further type inference. It supports recursion, but it has no pattern matching, and is a strict language (even though strict is something completely different).

In reply to Re^7: map and grep (but for hashes) by Corion
in thread map and grep (but for hashes) by zerohero

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