Benchmark: string concat speed

Script Preparation code:

var s;

Tests:

plus
s = Math.random() + "a"+" b" + " " + "cdefgh " + "test" + " "+"123";
join
s = [Math.random(), "a","b","cdefgh","test","123"].join(" ");
fn
function join(){ var s; for(var i=0, len=arguments.length;i<len;i++){ s += arguments[i] + " "; } return s; } join(Math.random(),"a","b","cdefgh","test","123");
spacer
function spacer(s){ return s+" "; } s = spacer(Math.random())+spacer("a")+spacer("b")+spacer("cdefgh")+spacer("test")+"123";

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
plus
join
fn
spacer

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):

LLMs can make mistakes. Check important info.

I'll break down the provided benchmark and explain what's being tested, compared, and considered.

**Benchmark Definition**

The benchmark definition is represented by two JSON objects: `Benchmark Definition` for each individual test case.

1. The first object defines a variable `s` with a string literal:
```javascript
s = Math.random() + "a" + "b" + " " + "cdefgh" + "test" + " " + "123";
```
This is simply a concatenation of strings, where the resulting string will be different each time the benchmark is run due to `Math.random()`.

2. The second object defines an array and uses the `join` method:
```javascript
s = [Math.random(), "a", "b", "cdefgh", "test", "123"].join(" ");
```
Here, the array elements are concatenated with spaces in between using the `join` method.

**Test Cases**

There are four test cases:

1. **plus**: This is a simple concatenation of strings using the same approach as the first benchmark definition.
2. **join**: As explained earlier, this uses an array and the `join` method to concatenate strings.
3. **fn**: This defines a custom function `join()` that takes multiple arguments and concatenates them with spaces in between.
4. **spacer**: This defines a custom function `spacer()` that takes a string as input and returns the same string followed by a space.

**Comparison**

The benchmark is comparing the performance of these four approaches:

* Simple concatenation using string literals
* Array-based concatenation using the `join` method
* Custom function for array-based concatenation (`fn`)
* Custom function for string manipulation (`spacer`)

Each approach has its own pros and cons:

* **Simple concatenation**: Easy to implement, but may not be efficient due to the creation of temporary strings.
* **Array-based concatenation with `join` method**: More efficient than simple concatenation, as it avoids creating temporary strings. However, it creates an array object, which can have overhead.
* **Custom function (`fn`) for array-based concatenation**: Provides more flexibility and control over the concatenation process. However, it may introduce additional overhead due to the creation of a custom function object.
* **Custom function (`spacer`)**: This is similar to `fn`, but only used for string manipulation.

**Library**

None of the benchmark cases use any external libraries or frameworks besides the standard JavaScript library.

**Special JS Features/Syntax**

There are no special JS features or syntax mentioned in the benchmark definition. However, it's worth noting that some modern JavaScript versions (e.g., ECMAScript 2015+) may have additional features and syntax not relevant to this benchmark.

**Alternatives**

Other alternatives for string concatenation could include:

* Using a template engine like Handlebars or Pug
* Using a library like Lodash's `string.join()` method
* Using a streaming approach to concatenate strings

However, these alternatives are not relevant to the current benchmark definition and may introduce additional complexity.

Overall, this benchmark is designed to compare the performance of different approaches for string concatenation in JavaScript.

Latest run results:

Run details: (Test run date: 7 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_9_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.95 Safari/537.36

Browser/OS: Chrome 55 on Mac OS X 10.9.5

View result in a separate tab

Test name	Executions per second
plus	925111.2 Ops/sec
join	695299.4 Ops/sec
fn	673442.6 Ops/sec
spacer	628844.2 Ops/sec

Related benchmarks:

string concat speed (version: 0)

Comparing performance of: plus vs join vs fn vs spacer

Created: 7 years ago by: Guest

Jump to the latest result

plus

join

fn

spacer

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):