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isNotNil ​

Checks if the given value is not null nor undefined.

This function can also serve as a type predicate in TypeScript, narrowing the type of the argument to ensure it is not nullable.

Signature ​

typescript
function isNotNil<T>(x: T | null | undefined): x is T;

Parameters ​

  • x (T | null | undefined): The value to test if it is not null nor undefined.

Returns ​

(x is T): True if the value is not null nor undefined, false otherwise.

Examples ​

typescript
import { 
isNotNil
} from 'js-utils-es/predicate';
// Here the type of `arr` is (number | undefined)[] const
arr
= [1,
undefined
, 3];
// Here the type of `result` is number[] const
result
=
arr
.
filter
(
isNotNil
);
// result will be [1, 3]

Source ​

Source • Docs • Test Case

Contributors ​

Changelog ​

No recent changes

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