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isBoolean

Checks if the given value is a boolean.

This function can also serve as a type predicate in TypeScript, narrowing the type of the argument to boolean.

Signature

typescript
function isBoolean(x: unknown): x is boolean;

Parameters

  • x (unknown): The value to test if it is boolean.

Returns

(x is boolean): True if the value is boolean, false otherwise.

Examples

typescript
const value1 = true;
const value2 = 0;
const value3 = 'abc';

console.log(isBoolean(value1)); // true
console.log(isBoolean(value2)); // false
console.log(isBoolean(value3)); // false

Released under the MIT License.