Benchmark: RegEx vs For Loop 4

HTML Preparation code:

var string = "passw)odas4gsdfsdf";

Script Preparation code:

var string = "passw)odas4gsdfsdf";

Tests:

For Loop
const FORBIDDEN_CHARACTERS = [`<`, `>`, `&`, `$`]; for (const character of FORBIDDEN_CHARACTERS) { const position = string.indexOf(character); if (position !== -1) { return INVALID; } }
RegEx
const FORBIDDEN_CHARACTERS = [`<`, `>`, `&`, `$`]; const forbiddenRegex = new RegExp(`[${FORBIDDEN_CHARACTERS.join('')}]`); const match = forbiddenRegex.exec(string); if (match) { return INVALID; }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
For Loop
RegEx

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36

Browser/OS: Chrome 120 on Linux

View result in a separate tab

Test name	Executions per second
For Loop	6136471.5 Ops/sec
RegEx	3430198.2 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks.

**Benchmark Definition**

The benchmark defines two test cases: `For Loop` and `RegEx`. The test cases are designed to measure the performance difference between using a for loop and regular expressions (Regex) in JavaScript. The benchmark uses a predefined string (`string`) that contains some forbidden characters (`<`, `>`, `&`, `$`). The goal is to find the first occurrence of any of these characters in the string.

**Options Compared**

The two test cases compare the performance of:

1. **For Loop**: A traditional for loop approach, where we iterate over an array of forbidden characters and check each character's presence in the string using `indexOf()`.
2. **Regular Expressions (RegEx)**: A regex-based approach, where we create a regular expression pattern using the forbidden characters and use the `exec()` method to search for matches in the string.

**Pros and Cons**

**For Loop Approach**

Pros:

* Easy to understand and implement
* Suitable for simple string operations

Cons:

* Can be slower than RegEx due to the overhead of iteration and `indexOf()` calls
* May not perform well on large strings or complex patterns

**RegEx Approach**

Pros:

* Fast and efficient, especially for complex patterns
* Allows for more precise matching using flags (e.g., `g` for global search)

Cons:

* Can be more challenging to implement and debug due to the complexity of regex syntax
* May require more resources (CPU, memory) for large strings or complex patterns

**Other Considerations**

* Both approaches have trade-offs in terms of performance, readability, and maintainability.
* For simple string operations, a for loop might be sufficient. However, for more complex cases, RegEx can provide significant performance benefits.

**Library Usage**

In the benchmark definition, we don't see any explicit library usage. The `String.indexOf()` method is part of the built-in JavaScript String prototype. The regex engine is also built into JavaScript.

However, if we were to use a third-party library for regular expressions, such as `regex-escape` or `regex-test`, it could potentially affect the benchmark results.

**Special JS Features/Syntax**

There are no special JS features or syntax mentioned in this benchmark definition. The code uses standard JavaScript features, such as `const`, `let`, and `for...of`.

Now that we've dissected the benchmark, let's explore some alternative approaches:

1. **Regex alternatives**: Other regex flavors like PCRE (Perl-Compatible Regular Expressions) or Oniguruma might offer improved performance for specific use cases.
2. **Optimized String Methods**: Some browsers and engines provide optimized string methods, such as `String.prototype.indexOf()` with a hint for the search direction (e.g., forward).
3. **Native JavaScript Functions**: Modern JavaScript engines often include native functions for common string operations, like `String.prototype.search()`.
4. **Just-In-Time (JIT) Compilation**: Some browsers and engines use JIT compilation to optimize performance-critical code.

Keep in mind that the choice of approach depends on the specific requirements of your project, such as readability, maintainability, and performance.

Related benchmarks:

RegEx vs For Loop 4 (version: 0)

-

Comparing performance of: For Loop vs RegEx

Created: 2 years ago by: Guest

Jump to the latest result

For Loop

RegEx

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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