Benchmark: endsWith vs Regex extension

Tests:

Regex
/\.(js)$/i.test("https://www.measurethat.net/Benchmarks/Fork.js")
endsWith
"https://www.measurethat.net/Benchmarks/Fork.js".endsWith("js")

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Regex
endsWith

Fastest: N/A

Slowest: N/A

Latest run results:

No previous run results

This benchmark does not have any results yet. Be the first one to run it!

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 MeasureThat.net and explore what's being tested in this specific benchmark.

**Benchmark Definition**

The benchmark is defined by two test cases:

1. `/\\.(js)$/i.test("https://www.measurethat.net/Benchmarks/Fork.js")`
2. `"https://www.measurethat.net/Benchmarks/Fork.js".endsWith("js")`

These test cases are designed to compare the performance of two approaches to checking if a string ends with ".js".

**Options Compared**

The benchmark is comparing two options:

1. **Regular Expression (Regex)**: The first test case uses a regular expression (`/\\.(js)$/i`) to check if the given string ends with ".js". This approach uses a pattern matching mechanism to search for the desired substring.
2. **String Method**: The second test case uses the `endsWith` method on the string itself to check if it ends with "js".

**Pros and Cons**

Here's a brief summary of the pros and cons of each approach:

1. **Regex**:
	* Pros: Flexible, can be used for more complex pattern matching.
	* Cons: Can be slower due to the overhead of compiling a regular expression, may not work as expected with some edge cases (e.g., null or undefined values).
2. **String Method (`endsWith`)**:
	* Pros: Typically faster and more efficient than using Regex.
	* Cons: Limited to checking if the string ends with a specific substring.

**Library and Purpose**

There is no explicit library mentioned in the benchmark definition, but it's likely that the `endsWith` method is implemented as part of the JavaScript standard library or a commonly used library like Lodash. The purpose of this method is to provide a simple way to check if a string ends with a specific substring.

**Other Considerations**

When using Regex to check if a string ends with ".js", it's essential to consider the `i` flag at the end of the pattern (`/\\.(js)$/i`). This flag makes the search case-insensitive and global, meaning it will match anywhere in the string, not just at the end.

**Special JS Feature or Syntax**

There are no special JavaScript features or syntax mentioned in this benchmark definition. The focus is on comparing two performance-optimized approaches to checking if a string ends with ".js".

**Alternatives**

Some alternative approaches to checking if a string ends with ".js" include:

1. Using the `lastIndexOf` method and subtracting the index from the length of the string.
2. Using a custom implementation that uses bitwise operations or other low-level optimizations.

However, these alternatives are not tested in this benchmark definition.

Related benchmarks:

endsWith vs Regex extension (version: 0)

Comparing performance of: Regex vs endsWith

Created: 5 years ago by: Guest

Jump to the latest result

Regex

endsWith

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):