or with hashes. 
&foo (bar=>"1");

sub foo {
    %args=@_;
    %defaults=(foo=>9, bar=>8, baz=>7);
    foreach ("foo", "bar", "baz") {
        defined ($args{$_})  || {$args{$_}= $defaults{$_}} ;
        print $args {$_}
    }
}

[download]


update : or better yet, with the keys that you expect the sub to know : 
&foo (bar=>"1");

sub foo {
    %args=@_;
    %defaults=(foo=>9, bar=>8, baz=>7);
    foreach (keys %defaults) {
        defined ($args{$_})  || {$args{$_}= $defaults{$_}} ;
        print $_ ," - ",$args {$_},"\n";
    }
}

[download]
update : or better yet, just like Fletch sez. Nice stuff.

In reply to Re: Default subroutine parameters (boo) by boo_radley
in thread Default subroutine parameters by thelenm

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