Benchmark: .includes vs .some

Script Preparation code:

var foo = ['a', 'b', 'c', 'd', 'e'];

Tests:

.includes
const bar = foo.includes('c');
.some
const bar = foo.some(item => item === 'c');

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
.includes
.some

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/17.3.1 Safari/605.1.15

Browser/OS: Safari 17 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
.includes	19323556.0 Ops/sec
.some	25181972.0 Ops/sec

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

LLMs can make mistakes. Check important info.

I'd be happy to explain the benchmark and its options.

**Benchmark Overview**

The benchmark measures the performance difference between two common array methods in JavaScript: `Array.prototype.includes()` and `Array.prototype.some()`. These methods are used to check if at least one element in an array meets a certain condition.

**Options Compared**

There are only two options compared in this benchmark:

1. **`includes()`**: This method checks if the specified value (`'c'`) is present in the array using the `in` operator.
2. **`some()`**: This method checks if at least one element in the array meets a certain condition (in this case, being equal to `'c'`). It returns `true` as soon as it finds an element that meets the condition.

**Pros and Cons**

**`includes()`**

Pros:

* Generally faster than `some()`, since it uses a linear search algorithm that stops as soon as it finds the target value.
* More readable, as it clearly expresses the intent of checking for presence in the array.

Cons:

* May be slower for large arrays with no matching elements, since it still performs a full scan.
* Not suitable for situations where you need to stop searching early if the condition is not met.

**`some()`**

Pros:

* Faster than `includes()` when there are no matching elements in the array, since it stops scanning once it finds an element that doesn't match.
* Suitable for situations where you need to stop searching early if the condition is not met.

Cons:

* May be slower than `includes()` for large arrays with at least one matching element, since it still performs a full scan.
* Less readable, as its behavior can lead to unexpected results in certain cases (e.g., if multiple elements match).

**Other Considerations**

* Both methods are generally supported by most modern browsers and JavaScript engines.
* The `some()` method is also commonly used with arrow functions, which can make it more concise but less readable.

**Library Used**

None of the benchmarking code uses any external libraries. It relies on built-in JavaScript features to execute the benchmarks.

**Special JS Feature or Syntax**

The benchmark does not use any special JavaScript features or syntax that would require prior knowledge of advanced topics. However, it assumes a basic understanding of array methods and their behavior.

**Alternatives**

If you need to compare performance between `includes()` and another method (e.g., `every()`, `forEach()`, etc.), or if you want to measure the performance of different implementation optimizations for these methods, you can modify the benchmark code accordingly.

Related benchmarks:

.includes vs .some (version: 0)

Comparing performance of: .includes vs .some

Created: 5 years ago by: Guest

Jump to the latest result

.includes

.some

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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