When working with React and utilizing the useEffect hook, you might encounter an error stating that the dependency list passed to useEffect is not an array literal. This error message can be puzzling, but understanding its causes and solutions can streamline your development process.

Understanding the Issue

In React, the useEffect hook allows you to perform side effects in function components. However, it requires a dependency array as its second argument to manage when the effect should be re-run.

How to Create the Issue

To create this issue, developers often mistakenly pass a variable or an expression that is not wrapped in an array as the dependency list to useEffect. This can lead to unexpected behavior and errors, especially when dealing with asynchronous operations or state changes.

useEffect(() => {
  // Effect logic...
}, dependency); // Incorrect usage: dependency is not an array

Root Cause of the Issue

The root cause of this issue lies in the dependency list provided to the useEffect hook. React expects this list to be an array literal containing variables or expressions that the effect depends on.

Solution 1: Ensure Dependency List is an Array Literal

To resolve this issue, ensure that the dependency list passed to useEffect is an array literal containing all the variables or expressions that the effect relies on.

useEffect(() => {
  // Effect logic...
}, [dependency]); // Correct usage: dependency is wrapped in an array

Solution 2: Split Effects into Multiple useEffect Hooks

In cases where the effect logic depends on different sets of variables, consider splitting them into multiple useEffect hooks with distinct dependency lists.

useEffect(() => {
  // Effect logic for first set of dependencies...
}, [dependency1]);

useEffect(() => {
  // Effect logic for second set of dependencies...
}, [dependency2]);

Solution 3: Use useCallback and useMemo Hooks

If your useEffect hook depends on functions or computed values, utilize the useCallback and useMemo hooks to memoize them and include them in the dependency list accordingly.

const memoizedFunction = useCallback(() => {
  // Memoized function logic...
}, [dependency]);

useEffect(() => {
  // Effect logic that depends on memoized function...
}, [memoizedFunction]);

Solution 4: Refactor Code to Minimize Dependencies

Consider refactoring your code to minimize the number of dependencies passed to useEffect, focusing only on the essential variables or state changes required by the effect.

const [state, setState] = useState(initialState);

useEffect(() => {
  // Effect logic...
}, [state]);

Solution 5: Use ESLint Plugins for Dependency Analysis

Integrate ESLint plugins such as eslint-plugin-react-hooks to statically analyze your code and detect issues like incorrect dependency lists in useEffect hooks during development.

npm install eslint-plugin-react-hooks --save-dev

Ensure that you configure ESLint to enforce the rules provided by the plugin in your project’s ESLint configuration file.

Solution 6: Utilize TypeScript for Type Safety

If you’re using TypeScript in your React project, leverage its type system to enforce correct usage of useEffect dependencies. TypeScript can provide compile-time checks and type safety, reducing the likelihood of passing incorrect dependency lists to useEffect.

import React, { useEffect } from 'react';

interface Props {
  dependency: any;

const Component: React.FC<Props> = ({ dependency }) => {
  useEffect(() => {
    // Effect logic...
  }, [dependency]); // TypeScript ensures correct dependency usage
  return <div>Component content</div>;

Ensure that you specify the correct types for props and dependencies to benefit from TypeScript’s type checking capabilities.

Solution 7: Document and Review Dependency Lists

Documenting the dependencies of useEffect hooks and conducting code reviews can help identify incorrect dependency lists early in the development process. Encourage team members to review and discuss the necessity of each dependency to avoid potential issues.

useEffect(() => {
  // Effect logic...
}, [dependency1, dependency2]); // Documented and reviewed dependencies

By fostering communication and collaboration within your development team, you can mitigate the risk of passing incorrect dependency lists to useEffect hooks.

Solution 8: Leverage ESLint Plugin React Hooks Rules

Take advantage of ESLint plugin react-hooks rules to enforce best practices and guidelines for using useEffect hooks. Configure ESLint to provide warnings or errors for incorrect usage of dependencies, promoting adherence to coding standards and improving code quality.

// Example ESLint configuration
  "plugins": ["react-hooks"],
  "rules": {
    "react-hooks/rules-of-hooks": "error",
    "react-hooks/exhaustive-deps": "warn"

Enforce rules such as “react-hooks/exhaustive-deps” to ensure exhaustive dependency lists in useEffect hooks, enhancing code reliability and maintainability.

By adopting these solutions and best practices, you can address the “React Hook useEffect” error effectively and optimize the performance and reliability of your React applications.