$_="abc";
$h{1+3}=41;
$h{a+3}=42;
$h{- length}=43;
$h[1+3]=41;
$h[a+3]=42;
$h[- length]=43;
$h[length]=44;
$,='|';
print %h,"\n",@h
__END__
-length|43|4|41|3|42|
|||43|44|41