I have a "sparse" AoA ref where each element may be either defined or undefined. I can flatten the entire structure using

@flat = map { @$_ } @{$aoa};

but is there a more efficient way to eliminate all the undefs right there inside the map() so I won't have to loop through the @flat array or invoke grep() to do it for me?

@flat = grep { defined } map { @$_ } @{$aoa};

I don't really know if this is even an issue, I'm just curious since practical uses of map() have always been a bit of a mystery for me.

-- Time flies when you don't know what you're doing

In reply to Flatten sparse AoA by FloydATC

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