Benchmark: Array concat vs spread operator vs push321

Tests:

Array.prototype.concat
var params = [ "hello", true, 7 ]; var other = [ 1, 2 ].concat(params);
spread operator
var params = [ "hello", true, 7 ] var other = [ 1, 2, ...params ]
Push
var params = [ "hello", true, 7 ]; var other = params.push(9);

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Suite status: <idle, ready to run>

Previous results

Test case name	Result
Array.prototype.concat
spread operator
Push

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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Let's break down the provided benchmark and explain what is being tested.

The main goal of this benchmark is to compare three different approaches for concatenating arrays in JavaScript:

1.  **`concat()` method**: This is the traditional way to concatenate arrays in JavaScript. It creates a new array by copying the elements from both arrays.
2.  **Spread operator (`...`)**: Introduced in ES6, the spread operator allows you to expand an array or object into individual elements when needed.
3.  **`push()` method**: This method adds one or more elements to the end of an array and returns the new length of the array.

**Comparison**

The benchmark compares these three approaches on different JavaScript engines (in this case, Chrome 88). The comparison is based on the number of executions per second for each approach. In general:

*   **`concat()` method**: This approach is generally slower than the spread operator and `push()` because it creates a new array.
    *   Pros: Works in all browsers, supports older JavaScript engines.
    *   Cons: Creates a new array, can be slower.
*   **Spread operator (`...`)**: This approach is usually faster than the `concat()` method because it does not create a new array. Instead, it modifies the existing array by adding new elements to its end.
    *   Pros: Faster than `concat()`, modifies original array, supports ES6+ browsers.
    *   Cons: May not work in older browsers or JavaScript engines that do not support spread operator.
*   **`push()` method**: This approach is faster than the `concat()` method because it does not create a new array. However, it can be slower than the spread operator for larger arrays because it requires updating the array's length and adding elements to its end.
    *   Pros: Faster than `concat()`, modifies original array.
    *   Cons: Can be slower than spread operator for large arrays.

**Library Usage**

There is no explicit library usage in this benchmark. However, if you need to use additional libraries or dependencies, Make sure they are included in the benchmark preparation code.

**Special JS Features/Syntax**

There are no special JavaScript features or syntax mentioned in this benchmark. The benchmark focuses on comparing different array concatenation approaches using standard JavaScript methods.

**Alternative Approaches**

If you want to explore alternative approaches for concatenating arrays in JavaScript, consider the following:

*   **Array methods**: In addition to `concat()`, `push()`, and spread operator, you can also use `slice()` or other methods that modify the array without creating a new one.
*   **Libraries**: Depending on your specific requirements, you might want to explore using specialized libraries like Lodash or Ramda for more efficient and expressive array operations.
*   **ES6+ features**: If you're targeting modern browsers or JavaScript engines, take advantage of ES6+ features like `flat()`, `flatMap()`, and other methods that provide more concise ways to work with arrays.

Keep in mind that each approach has its trade-offs, and the best choice depends on your specific use case, performance requirements, and compatibility considerations.

Related benchmarks:

Array concat vs spread operator vs push321 (version: 0)

Compare the new ES6 spread operator with the traditional concat() method and push

Comparing performance of: Array.prototype.concat vs spread operator vs Push

Created: 5 years ago by: Guest

Jump to the latest result

Array.prototype.concat

spread operator

Push

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):