Monks:

I have yet another general question. I'm working on debugging a perl program, and have been having to do a lot of reverse-engineering. With my primitive understanding of Perl this has been difficult, but I think I'm almost there. I just need (maybe) one piece of crucial information. Here is the subroutine I'm looking at:

sub SearchPubMed {
    my $InputRow = shift; # temporary! InputRow = SearchTermID
  my $QueryID = shift;
  my $CannedQueriesPurpose = shift;
  my $CannedQueriesQuery = shift;
  my $query;

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What exactly does it mean to define variables as shift? I understand that the shift operator grabs the first element of an array, and that when "shift" appears next to white space, it is assumed that it is grabbing from the @_ special array variable. I don't totally understand where @_ has come from here and what is stored in it. Can someone shed some light onto the @_ special variable for me? Thanks oodles.

In reply to shift operator by molly

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