Benchmark: test DomParser vs Regex vs IndexIf

Tests:

Dom Parser
const html = "<html><body><div>test</div></body></html>"; const parser = new DOMParser(); const virtualDom = parser.parseFromString(html, 'text/html'); const body = virtualDom.querySelector('body');
Regex
const html = "<html><body><div>test</div></body></html>"; const pattern = /<body[^>]*>((.|[\n\r])*)<\/body>/im; const matches = pattern.exec(html); const body = matches[1];
Loop
const html = "<html><body><div>test</div></body></html>"; const start = html.indexOf('>') + 1; const end = html.lastIndexOf('</'); const body = html.slice(start, end);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Dom Parser
Regex
Loop

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 9 months ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/139.0.0.0 Safari/537.36

Browser/OS: Chrome 139 on Windows

View result in a separate tab

Test name	Executions per second
Dom Parser	72058.6 Ops/sec
Regex	6984238.5 Ops/sec
Loop	33717036.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down the provided JSON and explain what is tested in each test case.

**Benchmark Definition**

The benchmark definition specifies that three different approaches will be compared: `DomParser`, `Regex`, and `Loop`. The goal is to determine which approach performs best in terms of execution speed.

**Test Cases**

Each test case defines a specific HTML string as input, and then describes how the input should be parsed using one of the three approaches.

1. **Dom Parser**: This test case uses the `DOMParser` API to parse the HTML string. Specifically, it creates a new instance of `DOMParser`, parses the HTML string using the `parseFromString` method, and then extracts the `<body>` element from the resulting virtual DOM document.
2. **Regex**: This test case uses regular expressions to parse the HTML string. It creates a pattern that matches the HTML string, executes the pattern on the input string using `pattern.exec`, and then extracts the matched substring.
3. **Loop**: This test case uses a simple loop-based approach to extract the `<body>` element from the HTML string. It finds the index of the first '>' character in the input string (representing the start of the `<body>` element) and then finds the index of the last '</' character (representing the end of the `<body>` element). The substring between these indices is extracted.

**Options Compared**

The three approaches are compared to determine which one performs best:

* **Dom Parser**: This approach uses the `DOMParser` API, which provides a more explicit and controlled way of parsing HTML documents. It may be slower due to its overhead.
* **Regex**: This approach uses regular expressions, which can be very fast but also prone to errors and performance issues if not implemented correctly.
* **Loop**: This approach is simple and lightweight but may be less accurate than the other two approaches.

**Pros and Cons**

* **Dom Parser**:
	+ Pros: More explicit and controlled parsing, better accuracy.
	+ Cons: May be slower due to its overhead.
* **Regex**:
	+ Pros: Very fast and lightweight.
	+ Cons: Prone to errors and performance issues if not implemented correctly.
* **Loop**:
	+ Pros: Simple and lightweight.
	+ Cons: Less accurate than the other two approaches.

**Library**

The `DOMParser` library is a built-in JavaScript API that provides a way to parse HTML documents programmatically. It's widely supported by modern browsers and can be used to extract specific elements or attributes from an HTML document.

**Special JS Feature/Syntax**

There are no special JavaScript features or syntaxes mentioned in the benchmark definition. All the approaches rely on standard JavaScript APIs and data structures.

**Other Alternatives**

If you're interested in exploring alternative approaches, some other options might include:

* Using a parsing library like `cheerio` or `html-parser`, which can provide more efficient parsing than the built-in `DOMParser` API.
* Using a different regular expression approach, such as using `String.prototype.matchAll()` instead of `pattern.exec()`.
* Implementing a custom loop-based parser that uses a different algorithm to extract the `<body>` element from the HTML string.

Related benchmarks:

test DomParser vs Regex vs IndexIf (version: 0)

Comparing performance of: Dom Parser vs Regex vs Loop

Created: 2 years ago by: Guest

Jump to the latest result

Dom Parser

Regex

Loop

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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