Benchmark: Array split vs string substring. For all split strings (v1)

Script Preparation code:

var n = 100
var s = new Array(n).fill("foo").join(".")

Tests:

Array.split
var n = s.split(".")[0];
Substring
var t = s var n = [] var idx = t.indexOf(".") while (idx > 0) { n.push(t.substring(0, idx)) t = t.substring(idx) idx = t.indexOf(".") }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Array.split
Substring

Fastest: N/A

Slowest: N/A

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

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Let's break down the provided JSON benchmark and its test cases.

**Benchmark Definition**

The benchmark is designed to compare two approaches for splitting a string into an array: `String.prototype.split()` (also known as "Array split") and manual substring extraction using `String.prototype.indexOf()` and `String.prototype.substring()`. The goal is to determine which approach is faster in all possible split strings.

**Options Compared**

The benchmark compares the performance of:

1. **Array Split**: Using the `split()` method, which returns an array of substrings.
2. **Manual Substring Extraction**: Using a loop with `indexOf()` and `substring()` methods to extract substrings from the original string.

**Pros and Cons**

**Array Split (split()):**

Pros:

* Easy to read and maintain
* Most developers are familiar with this method

Cons:

* May create intermediate arrays, which can lead to memory allocation overhead
* Performance may be slower for large inputs due to array creation

**Manual Substring Extraction:**

Pros:

* Can avoid creating intermediate arrays
* May offer better performance for large inputs

Cons:

* More complex and harder to read/maintain than the `split()` method
* Requires more manual memory management (in this case, no allocation is needed, but it's still a good point)

**Library Usage**

In both test cases, the benchmark uses `String.prototype.split()` and `String.prototype.indexOf()`, which are built-in JavaScript methods.

**Special JS Feature/Syntax**

None mentioned. However, note that some modern JavaScript engines (e.g., V8) have introduced additional features or optimizations for strings, but these are not directly related to this specific benchmark.

**Other Alternatives**

For a more extensive comparison, other approaches could be considered:

* **Regular Expressions**: Using `String.prototype.match()` and/or `String.prototype.exec()` with regular expressions to split the string.
* **Array Methods**: Using other array methods like `Array.prototype.filter()`, `Array.prototype.reduce()`, or `Array.prototype.map()` in combination with string manipulation functions.

Keep in mind that these alternatives may not be as straightforward or performant as the original "Array Split" and "Manual Substring Extraction" approaches.

Related benchmarks:

Array split vs string substring. For all split strings (v1) (version: 0)

Comparing performance of: Array.split vs Substring

Created: 3 years ago by: Guest

Jump to the latest result

Array.split

Substring

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

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