[Solved] operator ‘===’ cannot be applied to types ‘false’ and ‘true’

Question

Typescript is basically throwing an error there because it’s bad code.

true will never ever equal false. Typescript knows this, and tells you to fix your code.

Since these are constant values, they’re considered to be of the types true and false. The error message might be slightly confusing, but it’s correct, while giving a bit of an insight into the Typescript engine.

You’ll get a similar error for this code:

if (1 === 2) {}

Error:

Operator ‘===’ cannot be applied to types ‘1’ and ‘2’.

Comparing constants like these throws that error:

false === true; // Operator '===' cannot be applied to types 'false' and 'true'.
    1 === 2;    // Operator '===' cannot be applied to types '1' and '2'.
  "a" === "b";  // Operator '===' cannot be applied to types '"a"' and '"b"'.

Object.is is completely different from ===. Object.is performs no type coercion, and only compares both parameter’s value. Since TypeScript doesn’t validate those arguments with the function’s functionality, it doesn’t throw an error there.

Accepted Answer