What version of Perl are you running? length undef should return undef without warnings since 5.012 (April 2010), if I remember correctly.

map{substr$_->[0],$_->[1]||0,1}[\*||{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^*ARGV,3]

In reply to Re^3: Add value from one array element into another of same ID by choroba
in thread Add value from one array element into another of same ID by Anonymous Monk

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