Why Use Lodash _.each Over Native forEach

While native JavaScript provides Array.prototype.forEach for iterating over collections, Lodash's _.each (an alias for _.forEach) offers enhanced flexibility, safety, and functionality. This article explores why developers still rely on Lodash's implementation, highlighting key advantages such as native support for iterating over objects, the ability to exit loops early, and robust defense against null or undefined values.

Seamless Support for Objects and Arrays

The native Array.prototype.forEach method functions exclusively on arrays. To iterate over an object using vanilla JavaScript, developers must first transform the object into an array using Object.keys(), Object.values(), or Object.entries().

In contrast, _.each natively accepts both arrays and plain objects. When passed an object, it automatically traverses the object's own enumerable string keyed properties, passing the value, key, and the collection itself to the callback function:

const user = { name: 'Alice', role: 'Admin' };

// Iterates cleanly without Object.keys()
_.each(user, (value, key) => {
  console.log(`${key}: ${value}`);
});

Early Loop Termination

A well-known limitation of native forEach is that it cannot be stopped or broken out of; it will execute the callback for every single element unless an error is thrown.

Lodash solves this limitation by allowing early termination. Returning false from the iteratee function immediately exits the loop, functioning identically to a break statement in a standard for loop:

_.each([1, 2, 3, 4, 5], (num) => {
  if (num > 3) {
    return false; // Stops execution immediately
  }
  console.log(num);
});

Safe Handling of Null and Undefined

Attempting to run native forEach on a variable that resolves to null or undefined results in an uncaught TypeError: Cannot read property 'forEach' of undefined. To prevent application crashes, developers must write defensive checks or use optional chaining (e.g., data?.forEach(...)).

Lodash’s _.each handles null, undefined, and primitive values gracefully. If an invalid collection is supplied, the method simply skips execution without throwing a runtime error, reducing boilerplate validation code in data-fetching pipelines.

Predictable Iteration Over Sparse Arrays

Sparse arrays—arrays with missing indices or empty slots—can introduce subtle bugs in native iteration methods. Native forEach skips empty slots entirely without invoking the callback. Lodash standardizes iteration across different types of array-like structures and sparse collections, ensuring that behavior remains predictable across various JavaScript runtime environments.