Dear monks,
I have a function returning a hash, like 
sub func { return ('a' => 'ah', 'b' => 'be') };

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now I'd like to apply the internal perl function keys to this function. I tried 
keys func();
keys ( func() );
keys ( &func() );

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all of which give the following error: 
Type of arg 1 to keys must be hash (not subroutine entry)

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It works if I use a temporary variable though: 
my %hash = func();
keys %hash;

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Now is there a way I can use the function directly? Or doesn't Perl's syntax allow this? perldoc perlfunc gives following description:
Returns a list consisting of all the keys of the named hash. ...
which seems to imply I have to use a variable.

Thanks for any insights on this!

In reply to Apply function "keys" directly to function returning hash by wirrwarr

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