Benchmark: array.includes vs set.has for small n

Script Preparation code:

var a = [1, 2, 3];
var b = new Set(a)

Tests:

array includes
return a.includes(3)
set has
return b.has(9)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
array includes
set has

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/110.0.0.0 Safari/537.36

Browser/OS: Chrome 110 on Linux

View result in a separate tab

Test name	Executions per second
array includes	25747972.0 Ops/sec
set has	24607160.0 Ops/sec

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

LLMs can make mistakes. Check important info.

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

**What's being tested:**
The benchmark is comparing the performance of two approaches:

1. `array.includes` (test case 1)
2. `set.has` (test case 2)

Both tests are designed to check if a specific value (`3` in the first test and `9` in the second test) exists within an array or set, respectively.

**Approaches:**

### array.includes

`array.includes` is a method that searches for the existence of a specified value in an array. It iterates through the elements of the array until it finds the matching value (or reaches the end if not found). If the value exists, `includes` returns `true`, otherwise, it returns `false`.

**Pros:**

* Easy to understand and implement
* Works with arrays of any data type

**Cons:**

* Iterates through the entire array for each element check, making it slower than other approaches for large datasets.

### set.has

`set.has` is a method that checks if a specific value exists within a set. Sets are collections of unique values, so this operation is typically faster than searching an array since sets eliminate duplicates and have a more efficient data structure.

**Pros:**

* Fast lookup times due to the set's data structure
* Eliminates duplicate values, reducing the size of the search space

**Cons:**

* May not work with all types of data (e.g., arrays of mixed data types)
* Creates an additional object when creating a new set.

**Library and purpose:**
In this benchmark, `Set` is used as the underlying data structure for `set.has`. The `Set` library provides an efficient way to create and manipulate sets in JavaScript.

**Special JS feature or syntax:**
There are no special JavaScript features or syntax used in this benchmark. It's a straightforward comparison of two methods.

**Other alternatives:**

* For arrays, other alternatives could be:
	+ `indexOf()`: Similar to `includes`, but returns the index of the first occurrence instead of just a boolean value.
	+ `some()` and `every()`: These methods also iterate through the elements of an array, but with different conditions. `some()` returns `true` if at least one element matches the condition, while `every()` returns `true` only if all elements match the condition.
* For sets, other alternatives could be:
	+ Using a custom data structure like a hash table or a trie for fast lookup.

**Benchmarking considerations:**

* When testing these methods, it's essential to consider the size of the array or set being tested. The larger the dataset, the more significant the difference between `includes` and `has`.
* Additionally, the specific use case and requirements should be taken into account when designing benchmarks. For example, if you're searching for a specific value in an array, you might want to prioritize speed over memory usage.

In conclusion, this benchmark provides a straightforward comparison of two methods: `array.includes` and `set.has`. By understanding the strengths and weaknesses of each approach, developers can make informed decisions about which method to use in their own projects.

Related benchmarks:

array.includes vs set.has for small n (version: 0)

array.includes vs set.has for small n

Comparing performance of: array includes vs set has

Created: 3 years ago by: Guest

Jump to the latest result

array includes

set has

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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