If you want to check equality in JavaScript, there are two comparison operators, which are explained in depth in a previous article.
Very briefly, the double equals operator (==
) only compares
value whereas the triple equals operator (===
) compares both
value and type. But there is also a third option,
Object.is()
, which behaves the same as the triple equals
operator with the exception of NaN
and +0
and
-0
.
Here are some examples for additional clarity:
=== {}; // false
{} Object.is({}, {}); // false
1 === 1; // true
Object.is(1, 1); // true
+0 === -0; // true
Object.is(+0, -0); // false
NaN === NaN; // false
Object.is(NaN, NaN); // true