Benchmark: Dumb benchmark - MeasureThat.net

Tests:

.flatMap()
const arrayOfArrays = [{ a: [1, 2, 3] }, { a: [4, 5, 6] }]; const result = arrayOfArrays.flatMap(x => x.a);
.map() then .flat()
const arrayOfArrays = [{ a: [1, 2, 3] }, { a: [4, 5, 6] }]; const result = arrayOfArrays.map(x => x.a).flat();
.concat()
const arrayOfArrays = [{ a: [1, 2, 3] }, { a: [4, 5, 6] }]; const result = [].concat(...arrayOfArrays.map(x => x.a));

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
.flatMap()
.map() then .flat()
.concat()

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

**Overview of the Benchmark**

The provided benchmark measures the performance of three different approaches to flatten an array of arrays in JavaScript:

1. `flatMap()`
2. `.map()` followed by `.flat()`
3. Using the spread operator (`...`) with `.concat()`

Each test case uses a small, predefined array of arrays, which is created using the `arrayOfArrays` variable.

**Library and Special Features**

The benchmark does not use any external libraries, but it relies on the native JavaScript features mentioned above to achieve the desired functionality.

There are no special features or syntaxes used in this benchmark that are specific to a particular browser or JavaScript version.

**Options Compared**

Here's a brief explanation of each option compared:

1. **`flatMap()`**: This method was introduced in ECMAScript 2019 and allows flattening an array by applying a transformation function to each element of the array, without creating intermediate arrays.
2. **`.map()` followed by `.flat()`**: This approach uses the `map()` method to create a new array with the transformed elements, and then calls the `.flat()` method to flatten the resulting array.
3. **Using the spread operator (`...`) with `.concat()`**: This approach uses the spread operator to concatenate the arrays, effectively flattening them.

**Pros and Cons of Each Approach**

Here's a brief summary of the pros and cons of each approach:

1. **`flatMap()`**:
	* Pros: Efficient, concise, and modern syntax.
	* Cons: May have compatibility issues with older browsers or versions of JavaScript.
2. **`.map()` followed by `.flat()`**:
	* Pros: Widely supported across different browsers and versions of JavaScript. Easy to understand and implement for those familiar with array methods.
	* Cons: May be less efficient than `flatMap()` due to the creation of intermediate arrays.
3. **Using the spread operator (`...`) with `.concat()`**:
	* Pros: Works in older browsers and versions of JavaScript that don't support `flat()` or `flatMap()`. Can be a good fallback for situations where modern syntax is not supported.
	* Cons: May be less efficient than `flatMap()` due to the use of `concat()`, which creates a new array.

**Other Alternatives**

If you need to flatten arrays in JavaScript, here are some other alternatives:

1. **Using a loop**: You can use a simple loop to iterate over each element of the array and concatenate or push it to a new array.
2. **Using `reduce()`**: You can use the `reduce()` method to accumulate the elements of the array into a single array.
3. **Using `Array.prototype.flat()` (in modern browsers)**: If you're targeting modern browsers that support `flat()`, this method is often more efficient than using `concat()` or other approaches.

Keep in mind that these alternatives may have varying levels of compatibility and performance compared to the three options mentioned above.

Related benchmarks:

Dumb benchmark (version: 0)

Comparing performance of: .flatMap() vs .map() then .flat() vs .concat()

Created: 3 years ago by: Guest

Jump to the latest result

.flatMap()

.map() then .flat()

.concat()

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):