well, thats not the result I get:

sub defaults { 
    my( $p1, $p2, $p3) = map{ defined $_[0] ? shift : $_ }( 1, 2, 3 );
+ 
    print "p1:$p1; p2:$p2; p3:$p3\n"; 
};;
 
defaults('a', undef, 'c');

[download]

p1:a; p2:2; p3:3

$p3 ne 'c'

the first undef value omits the shift, all following parameters will be replaced by defaults! You need an explicit shift after the colon!

Cheers Rolf

In reply to Re^6: Correct idiom for default parameters by LanX
in thread Correct idiom for default parameters by mrider

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