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@technobuddha > library > Object > Type Guards

Function: isFunction()

ts
function isFunction(value: unknown): value is Function;

Defined in: is-function.ts:24

Determines whether the provided value is a function.

This includes regular functions, generator functions, async functions, and proxies that behave like functions. It uses both typeof and Object.prototype.toString checks to ensure accurate detection.

Parameters

ParameterTypeDescription
valueunknownThe value to test.

Returns

value is Function

True if the value is a function, otherwise false.

Example

typescript
isFunction(function() {}); // true
isFunction(() => {}); // true
isFunction(async function() {}); // true
isFunction(function* () {}); // true
isFunction(null); // false
isFunction({}); // false