return_ref, as its name announces, returns a reference to a hash. That reference gets assigned to a scalar variable ($ref) as is fine an proper. A rather bogus test for "truth" is then made to see if $_ is a reference to anything (is that what you thought the test actually was?).

I'm not sure what issue you are trying to illustrate, however the following code may provide a little illumination:

use strict;
use warnings;

my $scalar = 'a string is a scalar';

print ref ({}), "\n";
print ref ([]), "\n";
print ref (ret_hash ()), "\n";
print ref (ret_array ()), "\n";
print ">", ref ($scalar), "<\n";
print ref (\$scalar), "\n";

sub ret_hash {my %hash; return \%hash;}
sub ret_array {my @array; return \@array;}

[download]

Prints:

HASH
ARRAY
HASH
ARRAY
><
SCALAR

[download]

ref tells you something about the type of reference you point it at (but nothing about scalars). ref on it's own tells you about whatever reference $_ contains (which is the test you were making in your if).

DWIM is Perl's answer to Gödel

In reply to Re: Truthfulness of references by GrandFather
in thread Truthfulness of references by njcodewarrior

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