That the point of map. It takes a list of inputs, and produces a different list from those inputs. It does so by applying the transformation function (the block or expression) to each input, and collecting the outputs of that function.

Examples:

my @uc = ( uc("abc"), uc("def") );

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my @uc = map { uc($_) } "abc", "def";
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my %h = ( "abc" => 1, "def" => 1 );

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my %h = map { $_ => 1 } "abc", "def";
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