That doesn't cover his case for the empty string to also be defaulted; so:

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

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In reply to Re^2: Assigning default values to function arguments which may be �empty� by BrowserUk
in thread Assigning default values to function arguments which may be “empty” by Wyrdweaver

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