JSHint'nocomma'选项有什么作用？

Question

The documentation says :

This option prohibits the use of the comma operator. When misused, the comma operator can obscure the value of a statement and promote incorrect code.

But it's still not clear to me what scenario JSHint is looking for. Could somebody please provide an example?

Answer 1

MDN: Comma Operator

The comma operator evaluates each of its operands (from left to right) and returns the value of the last operand.

Example

function myFunc() {
  var message = "hello";

  return (message += "howareya", message);
}
// returns "hellohowareya"