Benchmark: Array.findFirst vs Map.has

Script Preparation code:

let array = [];
for (var i=0; i<300; ++i) {
  	array.push('00' + i);
}

function hasWithFindFirst(needle) {
	return array.findFirst(needle) !== undefined;
}

let map = {};
array.forEach(item => map[item] = true);

function hasWithMap(needle) {
	return needle in map;
}

Tests:

findFirst
for (var i=0; i<100; ++i) { hasWithFindFirst('404'); }
map
for (var i=0; i<100; ++i) { hasWithMap('404'); }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
findFirst
map

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/537.36 (KHTML, like Gecko) Chrome/119.0.0.0 Safari/537.36

Browser/OS: Chrome 119 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
findFirst	0.0 Ops/sec
map	410112.3 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks on MeasureThat.net!

**Benchmark Definition**

The provided JSON represents a benchmark definition, which describes two test cases: `Array.findFirst vs Map.has`. This benchmark compares the performance of using `Array.findFirst` with `Map.has`.

In this context:

* `Array.findFirst` is a method that returns the first element in an array that satisfies the provided condition.
* `Map.has` is a method that checks if a key exists in a Map object.

**Options Compared**

Two options are compared:

1. **Array.findFirst**: This option uses the `Array.findFirst` method to search for the specified value in the array.
2. **Map.has**: This option uses the `Map.has` method to check if the specified value exists in the Map.

**Pros and Cons of Each Approach**

* **Array.findFirst**
	+ Pros:
		- Easy to implement and understand.
		- Can be efficient for small arrays or specific use cases.
	+ Cons:
		- May not be as efficient as `Map.has` for large datasets, as it requires searching the entire array.
		- Can be slower due to the overhead of iterating over the array.
* **Map.has**
	+ Pros:
		- Generally faster than `Array.findFirst`, especially for large datasets.
		- More memory-efficient, as only the necessary keys are stored in the Map.
	+ Cons:
		- Requires a Map object to be created and populated with data.
		- May have additional overhead due to the creation and management of the Map.

**Library: `Array.prototype.findFirst`**

The `Array.prototype.findFirst` method is not a built-in JavaScript library, but rather an extension that can be added to arrays. It's likely that the MeasureThat.net benchmark tool provides this functionality or simulates it for testing purposes.

**Special JS Feature/ Syntax: `let` and `var` declarations**

In the provided code, both `let` and `var` declarations are used. The use of `let` is generally considered better practice than `var`, as it avoids variable hoisting and provides better scoping control. However, in this benchmark, both approaches are compared to see their relative performance.

**Other Considerations**

When writing benchmarks like this one, consider the following:

* **Test data size**: The benchmark size is relatively small (300 elements), which may not accurately represent real-world scenarios.
* **Browser and device variations**: The benchmark results are specific to a Chrome browser on a Mac OS X 10.15.7 system. Other browsers and devices might yield different results.
* **Interpretation of results**: When interpreting the results, consider the context in which this code will be deployed. Will it be used for small datasets or large-scale applications?

**Alternative Benchmarks**

For comparing similar performance characteristics, alternative benchmarks could include:

* `Array.prototype.indexOf` vs `Map.has`
* `Object.keys()` vs `for...in` loop
* `forEach()` vs `reduce()`

Related benchmarks:

Array.findFirst vs Map.has (version: 0)

Compare performance between Array.findFirst vs Map.has

Comparing performance of: findFirst vs map

Created: 2 years ago by: Guest

Jump to the latest result

findFirst

map

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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