Or how about a solution using a regular expression.

my @l1 = qw(Date IndexID Maturity OnTheRun CompositePrice 
CompositeSpread ModelPrice ModelSpread Depth Heat);

my @l2 = qw(OnTheRun CompositePrice CompositeSpread Depth);

my @l3;

{
    local $" = q{|};
    @l3 = map {m{^@l2$} ? $_ : q{null}} @l1;
}

[download]

Cheers,

JohnGG

In reply to Re: My 'perldar' tells me there is a 'better' solution for this list operation by johngg
in thread My 'perldar' tells me there is a 'better' solution for this list operation by OfficeLinebacker

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