map { split(" ", $arr->[$_]) } 0..$#{$arr} should do

Update: Rereading your question this is not what you're seeking for. Following will save also the index.

map { [ split(" ", $arr->[$_]." $_") ] } 0..$#{$arr};

But as pg already said, there is no obvious advantage in storing the index.

In reply to Re: Using Map to Create AoA by Dietz
in thread Using Map to Create AoA by neversaint

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