JSLint Expected '===' and instead saw '=='

Question

Recently I was running some of my code through JSLint when I came up with this error. The thing I think is funny about this error though is that it automatically assumes tha

Answer 1

JSLint is inherently more defensive than the Javascript syntax allows for.

From the JSLint documentation:

The == and != operators do type coercion before comparing. This is bad because it causes ' \t\r\n' == 0 to be true. This can mask type errors.

When comparing to any of the following values, use the === or !== operators (which do not do type coercion): 0 '' undefined null false true

If you only care that a value is truthy or falsy, then use the short form. Instead of

(foo != 0)

just say

(foo)

and instead of

(foo == 0)

say

(!foo)

The === and !== operators are preferred.