Comparing NaN values for equality in Javascript
if(val1 == val2 || (isNaN(val1) && isNaN(val2)))Nothing to improve. Just add the parentheses to make it clear to everyone.
Avoid isNaN. Its behaviour is misleading:
isNaN(undefined) // true_.isNaN (from Underscore.js) is an elegant function which behaves as expected:
// Is the given value `NaN`?// // `NaN` is the only value for which `===` is not reflexive._.isNaN = function(obj) { return obj !== obj;};_.isNaN(undefined) // false_.isNaN(0/0) // true
Try using Object.is(), it determines whether two values are the same value. Two values are the same if one of the following holds:
- both
undefined - both
null - both
trueor bothfalse - both strings of the same length with the same characters in the same order
- both the same object
- both numbers and
- both
+0 - both
-0 - both
NaN - or both non-zero and both not
NaNand both have the same value
- both
e.g. Object.is(NaN, NaN) => true
Refer to https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/is