all operators must return a value

All operators should return a value because of the definition of the term 'operator'. 
I could not find an operator as an exception which doesn't return a value.
Do you?

Author: lumosmind

1-js/02-first-steps/08-operators/article.md

@@ -219,7 +219,7 @@ alert( x ); // 5
 
 The fact of `=` being an operator, not a "magical" language construct has an interesting implication.
 
-Most operators in JavaScript return a value. That's obvious for `+` and `-`, but also true for `=`.
+All operators in JavaScript return a value. That's obvious for `+` and `-`, but also true for `=`.
 
 The call `x = value` writes the `value` into `x` *and then returns it*.