#!/usr/bin/perl -w
sub accum {
    my $curr = 0;
    sub {
        my $param = shift;
        $curr += $param;
    }
}
my $acc1 = accum();
print "a1 ",$acc1->(3),"\n";
print "a1 ",$acc1->(5),"\n";
my $acc2 = accum();
print "a2 ",$acc2->(1),"\n";
print "a1 ",$acc1->(2),"\n";
print "a2 ",$acc2->(7),"\n";
print "a1 ",$acc1->(10),"\n";
print "a2 ",$acc2->(4),"\n";
  
   back to test 
  
  (C) 1998-2017 Olaf Klischat  <olaf.klischat@gmail.com>