Arg! You're right. I tried it against my 5.10 version, because it was sitting there at the command prompt: 

sub test{ 
    my($p1,$p2,$p3) = map shift // $_,(1,2,3); 
    print "p1:$p1; p2:$p2; p3:$p3"; 
};;

[0] Perl> test();;
p1:1; p2:2; p3:3

[0] Perl> test( 'a', 'b', 'c' );;
p1:a; p2:b; p3:c

[0] Perl> test( 'a', , 'c' );;
p1:a; p2:c; p3:3

[0] Perl> test( 'a', undef, 'c' );;
p1:a; p2:2; p3:c

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Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
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In the absence of evidence, opinion is indistinguishable from prejudice.
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In reply to Re^7: Correct idiom for default parameters by BrowserUk
in thread Correct idiom for default parameters by mrider

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