I was pretty sure there was something for this in List::MoreUtils, but as it turned out there isn't. So I came up with this: 
sub insert_array_elem 
{
  my ($ra, $elem, $index) = @_; # insert $elem before $ra->[$index]
  my $idx = 0;

  insert_after { $idx++ == $index-1; } $elem => @{$ra};
}

[download]
This doesn't work for the edge cases (first and last element), but hey, that's what pop and friends are there for. Maybe you could write an email to the author of List::MoreUtils to provide an insert_at_index function?.


holli, /regexed monk/

In reply to Re: Linked lists as arrays: inserting values by holli
in thread Linked lists as arrays: inserting values by radiantmatrix

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