4 ms·
No, the correct way is to use the global function isNaN(x);
by some-1 14y ago
No, the correct way is to use the global function isNaN(x);
- grayrest 14y agoisNaN will return true for NaN and all values that coerce to it. The equals check will test ONLY for NaN itself: var x = "a"; isNaN(x); // true (x === x) === false // false x = NaN isNaN(x); // true (x === x) === false // true