Benchmark: arity 3 string join vs concat

Script Preparation code:

function surroundJoin(head, tail, str) { return [head, str, tail].join() }
function surroundConcat(head, tail, str) { return head.concat(str, tail) }
function surroundConcatConcat(head, tail, str) { return head.concat(str).concat(tail) }

const head = '('
const tail = ')'
const body = 'foobar'

Tests:

Join string parts
const str = surroundJoin('(', ')', 'foobar')
Concat string parts
const str = surroundConcat('(', ')', 'foobar')
Chained concat string parts
const str = surroundConcatConcat('(', ')', 'foobar')

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Join string parts
Concat string parts
Chained concat string parts

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/93.0.4577.82 Safari/537.36

Browser/OS: Chrome 93 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
Join string parts	5339307.0 Ops/sec
Concat string parts	11192565.0 Ops/sec
Chained concat string parts	15653316.0 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 benchmark and explain what's being tested.

**Benchmark Overview**

The benchmark compares three different approaches to concatenating strings in JavaScript: using `join()`, `concat()`, and chaining multiple `concat()` calls.

**Script Preparation Code**

The script preparation code defines three functions:

1. `surroundJoin(head, tail, str)`: This function takes three arguments: the head, tail, and a string (`str`) to be inserted between them. It uses the `join()` method to concatenate the arguments into a single string.
2. `surroundConcat(head, tail, str)`: This function is similar to `surroundJoin()`, but it uses the `concat()` method instead of `join()`.
3. `surroundConcatConcat(head, tail, str)`: This function chains multiple `concat()` calls to concatenate the arguments.

The script also defines three constants: `head`, `tail`, and `body`, which are used as test cases for each approach.

**Benchmark Definition JSON**

The benchmark definition JSON contains an array of objects, each representing a test case. Each object has two properties:

1. `Benchmark Definition`: This property specifies the JavaScript code to be executed for each test case.
2. `Test Name`: This property provides a descriptive name for each test case.

In this case, there are three test cases:

1. `Join string parts`: This test case executes the `surroundJoin()` function with `head`, `tail`, and `body` as arguments.
2. `Concat string parts`: This test case executes the `surroundConcat()` function with `head`, `tail`, and `body` as arguments.
3. `Chained concat string parts`: This test case executes the `surroundConcatConcat()` function with `head`, `tail`, and `body` as arguments.

**Library Usage**

None of the benchmark code uses any external libraries.

**Special JS Features or Syntax**

The only special feature used in this benchmark is the use of arrow functions (i.e., the `=>` syntax) in some of the script preparation code. However, since it's a simple benchmark, the impact of arrow functions on performance is likely negligible.

**Pros and Cons of Each Approach**

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

1. **Join()**: This method is generally faster than `concat()` because it avoids creating intermediate strings.
	* Pros: Fast, efficient
	* Cons: May not be suitable for all use cases (e.g., when working with large strings)
2. **Concat():** This method creates an array and then joins the elements together using `join()`.
	* Pros: Suitable for most use cases, easy to read and understand
	* Cons: Can be slower than `join()` due to intermediate string creation
3. **Chained Concat:** This approach chains multiple `concat()` calls together.
	* Pros: May have better cache locality due to the sequential nature of the operations
	* Cons: Can lead to unnecessary overhead due to the creation of intermediate arrays

**Alternatives**

If you wanted to rewrite this benchmark, you could consider the following alternatives:

1. Use a library like Lodash or Ramda, which provides optimized string concatenation functions (e.g., `lodash.join()`, `ramda.concat()`)
2. Compare the performance of other string concatenation methods, such as using template literals (`template literals`) or creating an array and then joining it together using `join()`
3. Use a more advanced benchmarking library, like Benchmark.js or jsperf, to measure performance in a more robust way

Related benchmarks:

arity 3 string join vs concat (version: 1)

Comparing performance of: Join string parts vs Concat string parts vs Chained concat string parts

Created: 3 years ago by: Registered User

Jump to the latest result

Join string parts

Concat string parts

Chained concat string parts

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):