#prototyped to explicitly state acceptable arguments

sub addstuff($$$);

...

#gives error if too few or too many arguments
#(or arguements of wrong type)
[download]

OTOH:

>perl -wMstrict -le
"my @ra = (99 .. 199);
 ;;
 sub S ($$$) {
   my $A = shift;  my $B = shift;  my $C = shift;
   ;;
   return $A + $B + $C;
   }
 ;;
 print S 1, 2, @ra;
"
104
[download]

Maybe better read Far More than Everything You've Ever Wanted to Know about Prototypes in Perl -- by Tom Christiansen first, then generally avoid prototypes.