The latter more or less does the same work as the former. However, the latter does all the work in Perl, while the former does it in C. However, the usual way of doing this is by using splice, which also does the same work, and also in C: 
    splice @a => $idx, 0 => $newitem;

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Note that they all take time linear in the size of the array. If you need to do a lot of insertions in a long list, you ought to review your algorithm, and see whether you really need to keep a sorted list. Perhaps a (balanced) tree will be better.

Abigail

In reply to Re: Shifting an Array by Abigail-II
in thread Shifting an Array by kelan

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