I tried 3 different ways to write a function returning an empty list. 

use strict;
use warnings;

sub empty_list1 {
  @{ [] }
}

sub empty_list2 {
  qw,,
}

sub empty_list3 {
  ()
}

$|=1;

print(scalar(empty_list1()),"\n");
print(scalar(empty_list2()),"\n");
print(scalar(empty_list3()),"\n");

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For the print, the function is called in scalar context, so that the number of list elements should be printed. I thought the 3 variants are equivalent, but only for the first I get the expected value of 0. In the other two cases, Perl complains about uninitialized value being used.

I understand that in the first case, the return expression is an empty array, while in the non-working case, it is an empty list, but I don't understand the implications here.
-- 
Ronald Fischer <ynnor@mm.st>

In reply to Empty List miracle(1) by rovf

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