Why does !1 give me nothing in Perl?

Question

This is strange. The following:

$sum = !0;
print $sum;

prints out 1 as you would expect. But this

$sum = !1;
print $sum;
         


        

Answer 1

The operators that only return a boolean result will always return 1 for true and a special false value that's "" in string contexts but 0 in numeric contexts.