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#!/usr/bin/perl -w
&foo; # the function call to foo with no parameters
&foo(1);
&foo("How's about a piZza?!");
&foo("JAPH");
sub foo
{
  if(@_)
  {
    my $varYouPassed=$_[0];
    print "You passed the var $varYouPassed to foo.";
  }
  else
  {
    print "You passed no vars to foo"
  }
}
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