What is the most efficient (or most elegant, for that matter) way of interleaving lists in Perl? For example, let's say I have two lists:

( 'blorke', 'gromble', 'poomba' ) and ( 'snork', 'dumble', 'gronke' ). I'd like to end up with:

( 'blorke', 'snork', 'gromble', 'dumble', 'poomba', 'gronke' )

In my case, I'm filling a hash, but I can think of other reasons to do this as well.

I'd prefer if it were self-contained (i.e. had no need for temporary or index variables).

One obvious solution:

my @list1 = ( 'blorke', 'gromble', 'poomba' );
my @list2 = ( 'snork', 'dumble', 'gronke' );
my %index = map { $_ => pop @list2 } (@list1);

[download]

...but that's destructive of @list2 (and I rather feel like it violates the spirit of map ... should probably have used for). Are there better (maybe non-destructive) ways?

In reply to interleaving lists by Anonymous Monk

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