The output (below) shows that the attempt to assign a new hashref fails silently.

No, it works:

sub assign_new_href {
    my $href = shift;
    $href = { new_key => 4 } ;
}

[download]

Within that function, you do assign a new hash reference to the lexical $href. However it doesn't modify the hash to which $href refers because that's not how references work. Think of $href as a container. You've dumped out its contents to replace those contents with something else. What you want to do is replace the contents of its contents with something else:

sub assign_new_href {
    my $href = shift;
    %$href = ( new_key => 4 );
}

[download]

Improve your skills with Modern Perl: the free book.

In reply to Re: Pass by reference question... by chromatic
in thread Pass by reference question... by freddo411

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