isWorkletFunction

isWorkletFunction checks if a function is a worklet function. It only works with Reanimated Babel plugin enabled. Unless you are doing something with internals of Reanimated you shouldn't need to use this function.

Reference

import { isWorkletFunction } from 'react-native-worklets';

const workletFunction = () => {
    'worklet';
    return 1;
};

const isWorkletFunction = isWorkletFunction(workletFunction);

console.log(isWorkletFunction); // true

const nonWorkletFunction = () => {
    return 1;
};

const isNonWorkletFunction = isWorkletFunction(nonWorkletFunction);

console.log(isNonWorkletFunction); // false

Type definitions

type WorkletClosure = Record<string, unknown>;

export type WorkletStackDetails = [
  error: Error,
  lineOffset: number,
  columnOffset: number,
];

interface WorkletInitData {
  code: string;
  /** Only in dev builds. */
  location?: string;
  /** Only in dev builds. */
  sourceMap?: string;
  /** Only in dev builds. */
  version?: string;
}

interface WorkletProps {
  __closure: WorkletClosure;
  __workletHash: number;
  __initData: WorkletInitData;
  __init?: () => unknown;
  /** `__stackDetails` is removed after parsing. */
  __stackDetails?: WorkletStackDetails;
}

type WorkletFunction<
  TArgs extends unknown[] = unknown[],
  TReturn = unknown,
> = ((...args: TArgs) => TReturn) & WorkletProps;

function isWorkletFunction<
  Args extends unknown[] = unknown[],
  ReturnValue = unknown,
>(value: unknown): value is WorkletFunction<Args, ReturnValue>

Arguments

value

A function to check if it is a worklet function.

Returns

isWorkletFunction returns a boolean value.

Remarks

• Do not call it before the worklet is declared, as it will always return false then.

  isWorkletFunction(myWorklet); // Will always return false.
  
  function myWorklet() {
    'worklet';
  }