Benchmark: Array concat vs spread operator vs push with object

Tests:

Array.prototype.concat
var params = [ { one: 1 }, { two: 2 }, { three: 3} ]; var other = [ { four: 4 }, { five: 5 }].concat(params)
spread operator
var params = [ { one: 1 }, { two: 2 }, { three: 3} ]; var other = [ { four: 4 }, { five: 5 }, ...params ]
Push
var params = [ { one: 1 }, { two: 2 }, { three: 3} ]; var other = [ { four: 4 }, { five: 5 }].push(...params);

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Suite status: <idle, ready to run>

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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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**Overview**

The provided JSON represents a JavaScript microbenchmark on MeasureThat.net, which compares the performance of three approaches for concatenating or pushing an array with another array in JavaScript.

**Benchmarked Approaches**

Three approaches are compared:

1. **`Array.prototype.concat()`**: This is a traditional method for concatenating two arrays in JavaScript. It creates a new array and copies the elements from both arrays into it.
2. **Spread Operator (`...`)**: Introduced in ES6, this operator allows you to expand an array into individual elements. In this benchmark, it's used to concatenate two arrays by spreading the first array into the second array.
3. **`Array.prototype.push()` with spread operator (`...`)**: This approach uses the `push()` method to add elements to an array and spreads the elements of another array into the existing array using the spread operator.

**Pros and Cons of Each Approach**

*   **`Array.prototype.concat()`**:
    *   Pros: Simple, widely supported, and easy to understand.
    *   Cons: Creates a new array, which can be memory-intensive for large datasets. It also copies the elements from both arrays, potentially leading to slower performance due to copying.
*   **Spread Operator (`...`)**:
    *   Pros: More concise, efficient in terms of memory usage, and often faster than `concat()`.
    *   Cons: Less intuitive for some developers, especially those familiar with traditional array methods. It also relies on the spread operator being supported by all browsers.
*   **`Array.prototype.push()` with spread operator (`...`)**:
    *   Pros: Similar to spread operator approach but avoids the need to create a new array.
    *   Cons: Slower than spread operator alone due to the overhead of `push()` method calls.

**Library Usage**

None of the benchmarked approaches rely on any libraries.

**Special JS Features/Syntax**

The benchmarks use the spread operator (`...`), which is a modern JavaScript feature introduced in ES6. It allows you to expand an array into individual elements, making it more concise and efficient than traditional methods like `concat()` or `push()`.

**Other Alternatives**

For concatenating arrays, other approaches include:

*   Using the `Array.prototype.push()` method with multiple arguments (e.g., `arr.push(...other)`)
*   Utilizing libraries like Lodash's `_.concat()` function
*   Leveraging modern array methods like `flat()` or `flatMap()`

However, these alternatives may not be as efficient or concise as the spread operator approach in terms of performance and readability.

**Best Practice**

When working with arrays in JavaScript, consider using the spread operator for concatenation due to its efficiency and conciseness. However, be mindful of browser support and potential issues with older versions of Internet Explorer.

Related benchmarks:

Array concat vs spread operator vs push with object (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: 3 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):