Suppose a function f() returns an even-sized list e.g.

sub f {a=>1,b=>2}

I'd like to interpret the list as a hash and list the keys with something like

say for keys f;

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but this will produce an error - "Experimental keys on scalar is now forbidden" (I'm running perl 5.33.9). I've found what does work is 

say for keys %{{f}};

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but I find this kind of inelegant. I'm far far from a monk so bear with me, but I can't see why 'keys' doesn't provide list context.

Also, is there a way of creating a hash for consumption by 'keys' in the above situation which doesn't involve creating a hash reference from a list and then immediately dereferencing?

In reply to Using 'keys' on a list by lammey

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