Benchmark: new RegExp mem test

Script Preparation code:

var reConstructor = new RegExp('^[0-9a-fA-F]{24}$')
var reSimpleConstructor = RegExp('^[0-9a-fA-F]{24}$')
var reLiteral = /^[0-9a-fA-F]{24}$/

Tests:

literal
reLiteral.test('132abc67219f019afe12901a')
RegExp
reSimpleConstructor.test('132abc67219f019afe12901a')
Constructor
reConstructor.test('132abc67219f019afe12901a')

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
literal
RegExp
Constructor

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

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

**Benchmark Definition JSON**

The provided JSON defines a JavaScript microbenchmark that tests different approaches to creating regular expressions in JavaScript. The three options being compared are:

1. **Literal**: A literal string is used directly in the regex pattern.
2. **Simple RegExp**: A new `RegExp` object is created using the `RegExp` constructor, passing the same string as its argument.
3. **Constructor**: Another approach is to create a regular expression constructor function and then call it with the desired pattern.

The script preparation code defines these three constructors:

* `reLiteral`: A literal string used directly in the regex pattern.
* `reSimpleConstructor`: A simple `RegExp` object created using the `RegExp` constructor.
* `reConstructor`: A custom regular expression constructor function.

**Pros and Cons of each approach**

1. **Literal**: This approach is likely to be the fastest since it avoids creating a new RegExp object. However, it may not provide a clear advantage over other approaches if the regex pattern is complex or requires optimization.
2. **Simple RegExp**: Creating a simple `RegExp` object using the constructor can provide some benefits, such as avoiding unnecessary memory allocations and improving cache locality. However, this approach still involves creating a new object, which might incur some overhead.
3. **Constructor**: The custom constructor function approach may provide the most control over optimization and caching. However, it introduces an additional layer of complexity and potential performance overhead due to the creation of a new function.

**Other considerations**

The benchmark also includes two test cases:

* `reLiteral.test('132abc67219f019afe12901a')`: Tests the literal approach with a specific input string.
* `reSimpleConstructor.test('132abc67219f019afe12901a')` and `reConstructor.test('132abc67219f019afe12901a')`: Test the simple RegExp and custom constructor approaches, respectively.

**JavaScript features used**

The benchmark uses JavaScript's regular expression syntax and object creation mechanisms to create and test the different constructors. Specifically, it utilizes:

* The `RegExp` constructor to create new regular expression objects.
* The `test()` method on a regular expression object to evaluate strings against it.
* Custom function creation using the `function` keyword.

**Library usage**

There are no external libraries used in this benchmark.

**Special JavaScript features and syntax**

The custom constructor approach uses a feature of JavaScript called "arrow functions" (introduced in ECMAScript 2015) to define the regular expression constructor function.

Latest run results:

Run details: (Test run date: 4 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/83.0.4103.116 Safari/537.36

Browser/OS: Chrome 83 on Mac OS X 10.13.6

View result in a separate tab

Test name	Executions per second
literal	6191115.5 Ops/sec
RegExp	5552362.5 Ops/sec
Constructor	5835731.0 Ops/sec

Related benchmarks:

new RegExp mem test (version: 0)

Comparing performance of: literal vs RegExp vs Constructor

Created: 4 years ago by: Guest

Jump to the latest result

literal

RegExp

Constructor

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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