I've recently been going through a number of the exercises at ProjectEuler. I did find it amusing that some questions turn out to be a one-liner in Perl.

On the other hand, I imagine many people, Perlers or otherwise, would require some hep with

my $sum = reduce {$a + $b } map { .... } grep { ...... } @some_array
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Yes, it can be broken into an explicit block, spread of several lines. Besides being more verbose and slower, the block focuses on what happens element by element, while the dense version thinks in terms of the data set.