You can also used defined() directly:

use warnings;
use strict;

print f() ."\n";
print f('hi') ."\n";

sub f {
    my $arg = defined $_[0] ? shift : 'default';
}

[download]

output:

default
hi

[download]

In reply to Re: Assigning default values to function arguments which may be “empty” by stevieb
in thread Assigning default values to function arguments which may be “empty” by Wyrdweaver

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