Benchmark: Array.prototype.join vs JSON.stringify

Script Preparation code:

var elements = [];

for (let i=32; i<10000; i++){
  elements.push(`${i}-${String.fromCharCode(i)}`);
}

Tests:

JSON.stringify
const output = JSON.stringify(elements);
Array.prototype.join
const output = elements.join();

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
JSON.stringify
Array.prototype.join

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 3 years ago)

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/78.0.3904.70 Safari/537.36

Browser/OS: Chrome 78 on Linux

View result in a separate tab

Test name	Executions per second
JSON.stringify	3295.2 Ops/sec
Array.prototype.join	2897.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks!

The provided benchmark compares two approaches to concatenate arrays: `JSON.stringify` and `Array.prototype.join`. To understand this, let's break down what each approach does:

**JSON.stringify**

`JSON.stringify()` is a method that converts a JavaScript object (including arrays) to a JSON string. When called on an array, it recursively traverses the elements of the array and concatenates them with commas in between.

In the benchmark preparation code, we create an array `elements` containing strings like `"i-${String.fromCharCode(i)}"`, where `i` is an integer from 32 to 99. The idea is that we're testing the performance of `JSON.stringify()` when dealing with a large array of string concatenations.

**Array.prototype.join()**

`Array.prototype.join()`, on the other hand, is a method that concatenates all elements in an array into a single string, separated by a specified separator (in this case, no separator).

In the benchmark preparation code, we create the same `elements` array as before. The idea is to test the performance of `Array.prototype.join()` when dealing with a large array of strings.

Now, let's discuss the pros and cons of each approach:

**JSON.stringify()**

Pros:

* Simple to implement: `JSON.stringify()` is a built-in method that doesn't require any additional logic.
* Fast: `JSON.stringify()` is generally faster than `Array.prototype.join()` because it uses a more efficient algorithm.

Cons:

* May not be the best choice for string concatenation: While `JSON.stringify()` can concatenate strings, its primary purpose is to serialize JavaScript objects. Using it for string concatenation may lead to unexpected behavior or performance issues.
* May not work as expected with large arrays: As the array size increases, `JSON.stringify()` may start using a more complex algorithm that's slower than necessary.

**Array.prototype.join()**

Pros:

* Designed for string concatenation: `Array.prototype.join()` is optimized for concatenating strings, making it a good choice for this use case.
* Handles large arrays well: As the array size increases, `Array.prototype.join()` adapts its algorithm to maintain performance.

Cons:

* Requires additional logic: Implementing `Array.prototype.join()` requires creating an iterator over the array elements and concatenating them with the specified separator.
* May be slower than `JSON.stringify()`: While `Array.prototype.join()` is optimized for string concatenation, it may still be slower than `JSON.stringify()` due to the additional logic required.

In the provided benchmark result, we can see that:

* `JSON.stringify()` performs slightly better (3295.1767578125 executions per second) compared to `Array.prototype.join()` (2897.04736328125 executions per second).

However, it's essential to note that these results may vary depending on the specific use case, system configuration, and JavaScript engine used.

Other alternatives for string concatenation in JavaScript include:

* Using a library like Lodash or Underscore.js, which provide optimized `join()` functions.
* Implementing a custom string concatenation function using a loop or other optimization techniques.
* Using a different data structure, such as a StringBuilder-like class, to concatenate strings.

Overall, the choice between `JSON.stringify()` and `Array.prototype.join()` depends on the specific requirements of your use case. If you're dealing with simple string concatenations, `Array.prototype.join()` might be a better choice. However, if you're working with complex data structures or performance-critical code, `JSON.stringify()` might be more suitable.

Related benchmarks:

Array.prototype.join vs JSON.stringify (version: 0)

Array.prototype.join vs JSON.stringify

Comparing performance of: JSON.stringify vs Array.prototype.join

Created: 4 years ago by: Guest

Jump to the latest result

JSON.stringify

Array.prototype.join

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):