The issue is that keys requires a hash (or an array), but you are (attempting to) provide it a bunch of scalars.

But while keys doesn't help, working with such data is exactly the purpose of the pair* functions in core module List::Util. 

say for pairkeys f;

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You could also use grep, but it's a bit inelegant. 

sub pairkeys { my $i = 0; grep { $i ^= 1 } @_ }

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Seeking work! You can reach me at ikegami@adaelis.com

In reply to Re: Using 'keys' on a list by ikegami
in thread Using 'keys' on a list by lammey

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