Sorry, I don't follow?

Passing undef gives exactly the effect I would expect and desire. That of accepting the default for that parameter: 

test( 'a', undef, 'c' );;
p1:a; p2:2; p3:c

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In reply to Re^5: Correct idiom for default parameters by BrowserUk
in thread Correct idiom for default parameters by mrider

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