isDefined

isDefined<T>(x): x is T

Checks if x is not null or undefined.

Example

isDefined(true)
// => true

isDefined("1234")
// => true

isDefined(undefined)
// => false

isDefined(null)
// => false

Type Parameters

• T

The type of x.

Parameters

x

The value to check.

undefined | null | T

Returns

x is T

false if x is a undefined or null, true otherwise.