Benchmark: Object.assign vs spread operator vs foreach set

Tests:

Object.assign
var params = { b:"hello", c: true, d:7 }; var old = {a: 2, b: "somthing"}; var other = Object.assign(old, params);
spread operator
var params = { b:"hello", c: true, d:7 }; var old = {a: 2, b: "somthing"}; var other = { ...old , ...params };
foreach
var params = [ ["b", "hello"], ["c", true], ["a", 5] ]; var other = {a: 2, b: "somthing"}; params.forEach(style => { other[style[0]] = style[1]; });

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Suite status: <idle, ready to run>

Previous results

Test case name	Result
Object.assign
spread operator
foreach

Fastest: N/A

Slowest: N/A

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Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):

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Measuring JavaScript performance is an essential task, and having a benchmarking tool like MeasureThat.net can be incredibly helpful.

**Benchmark Definition:**

The provided JSON defines three individual test cases to compare the performance of different approaches for merging objects or arrays:

1. **Object.assign**: The traditional method of merging two objects using the `Object.assign()` method.
2. **Spread Operator (`...`)**: A newer method of merging objects or arrays using the spread operator (`{ ...old, ...params }` or `{ ...[style] }`).
3. **`forEach` loop**: Using a `forEach` loop to iterate over an array and merge its elements into another object.

**Options compared:**

These three approaches are being compared to determine which one is the most efficient in terms of execution speed.

**Pros and Cons of each approach:**

1. **Object.assign**:
	* Pros:
		+ Widely supported and well-established method.
		+ Easy to understand and implement.
	* Cons:
		+ Can be slower due to its synchronous nature.
		+ May not perform as well with large datasets.
2. **Spread Operator (`...`)**:
	* Pros:
		+ Newer and more modern approach, making it potentially faster.
		+ Reduces the need for explicit loops or recursive functions.
		+ More concise and readable code.
	* Cons:
		+ Less widely supported at the time of its introduction (pre-2017).
		+ May not work as expected with older browsers or versions of Node.js.
3. **`forEach` loop**:
	* Pros:
		+ Allows for more control over the merging process.
		+ Can be faster than `Object.assign()` and spread operator, especially for large datasets.
	* Cons:
		+ More verbose and requires understanding of array iteration.
		+ May not be as readable or maintainable as other approaches.

**Library or special JS feature:**

In this benchmark, none of the individual test cases rely on a specific library. However, it's essential to note that some browsers may optimize `Object.assign()` differently due to its use in various libraries and frameworks (e.g., React).

**Considerations:**

When evaluating performance-critical code or writing high-performance JavaScript applications, consider factors such as:

* The size of the input data.
* The complexity of the merging process.
* The specific requirements of your application.

**Alternative approaches:**

Other methods for merging objects or arrays in JavaScript include:

1. **Lodash's `merge()` method**: A popular utility library that provides a fast and efficient way to merge objects or arrays.
2. **Immutable.js's `fromPairs()` function**: A immutable data structure library that allows for efficient merging of pairs.
3. **Recursive functions**: Manual implementation using recursive functions can be an option, especially when working with small datasets.

When choosing an approach, consider the trade-offs between performance, readability, and maintainability, as well as any specific requirements or constraints of your application.

Related benchmarks:

Object.assign vs spread operator vs foreach set (version: 0)

Comparing performance of: Object.assign vs spread operator vs foreach

Created: 3 years ago by: Guest

Jump to the latest result

Object.assign

spread operator

foreach

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):