It's cheaper to return a ref to a structure than to return a copy of the structure. Database operations often return large structures and the cost of copying them could impose a significant cost of doing business.

You can use a reference pretty much anywhere you might otherwise use a structure directly. You may find References quick reference helps.

DWIM is Perl's answer to Gödel

In reply to Re: Why a reference, not a hash/array? by GrandFather
in thread Why a reference, not a hash/array? by Cody Pendant

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