Question

I wanted to chop off all but the first five elements of an array, so I stupidly did:

@foo = @foo[ 0 .. 4 ];

and heartily praised my own cleverness. But that broke once @foo ended up with only three elements, because then I ended up with two undefs on the end, instead of a three-element array. So I changed it to:

@foo = @foo > 5 ? @foo[ 0 .. 4 ] : @foo;

This works but is kinda ugly. Is there a better idiom for saying “give me everything up to the first five elements of the array?”

Answer 1

You can set the last index of an array to shorten or lengthen it. Like your code you’ll need to check to make sure your not creating undef elements.

$#foo = 4 if $#foo > 4;