Benchmark: 3xif||regexp - MeasureThat.net

3xif||regexp (version: 0)

Test the performance of replace() vs substring() vs slice() when replacing a char at the beginning of a (in this case uri query-)string that may or may not be there. Added the combined brackets[ ] + substr() method, since it's always the first char we wan't to pop off. Inspired by https://jsperf.com/replace-or-substr. Note: could not get 'let' and 'const' to work. Well, too bad...

Comparing performance of: if vs regex vs rexex2 vs regex3

Created: 3 years ago by: Guest

Jump to the latest result

Script Preparation code:

var strIn = 'https://www.data-xata.com/all-servers.html';

Tests:

if
if(strIn.endsWith('.html')) {} if(strIn.endsWith('.htm')) {} if(strIn.endsWith('/')) {}
regex
/(\.html|\.htm|\/)$/.test(strIn)
rexex2
/\/$|\.html?$/.test(strIn)
regex3
/(\.html|\.htm)$/.test(strIn); /\/$/.test(strIn)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
if
regex
rexex2
regex3

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 28 days ago):

LLMs can make mistakes. Check important info.

Measuring the performance of various approaches in JavaScript can be helpful for developers to choose the most efficient method for their specific use cases.

**Benchmark Definition**

The provided JSON defines two main benchmarks:

1. **Replace() vs substring() vs slice()**: This benchmark tests the performance of three different methods to replace a character at the beginning of a string:
	* `replace()` with regular expression (regex)
	* `substring()` with regex
	* A combined method using brackets and `substr()` to extract the first character, which is then replaced.
2. **Testing for a specific pattern**: This benchmark tests four different methods to check if a string ends with a specific pattern:
	* Using the `endsWith()` method
	* Using a single regex (`/\\.html|\\.htm$/`)
	* Using another regex (`/(\\.html|\\.htm)$/.test(strIn)`) (which is equivalent to the first one)
	* Using two separate regexes (`/\\.html$` and `/\\/$`).test(strIn)`

**Options compared**

The benchmark compares the performance of four options:

1. `replace()` with regex
2. `substring()` with regex
3. A combined method using brackets and `substr()`
4. Checking for a specific pattern using `endsWith()`, single regex, or two separate regexes

**Pros and Cons**

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

1. **`replace()` with regex**:
	* Pros: Easy to implement, flexible syntax
	* Cons: May be slower than other methods, can lead to unexpected results if not used correctly
2. **`substring()` with regex**:
	* Pros: Can be faster than `replace()`, but may require more complex syntax
	* Cons: Less intuitive than `replace()`, and may not work as expected if the pattern is not matched
3. **Combined method using brackets and `substr()`**:
	* Pros: Efficient, easy to implement
	* Cons: May be less flexible than other methods, requires additional processing steps
4. **Checking for a specific pattern using `endsWith()`**, single regex, or two separate regexes:
	* Pros: Easy to understand, can be faster than the combined method
	* Cons: May not work correctly if the string does not end with the expected pattern

**Libraries and Special JavaScript Features**

The benchmark uses the following libraries:

* None explicitly mentioned in the provided code, but `String.prototype.endsWith()` is used.

No special JavaScript features are mentioned, apart from using regex patterns. However, it's worth noting that some older browsers may have limited support for modern JavaScript features like arrow functions, let and const, which were not fully supported in Firefox 86 during this benchmark run.

**Alternatives**

Other alternatives to consider when replacing a character at the beginning of a string or checking for a specific pattern include:

* Using `String.prototype.startsWith()` instead of `endsWith()`
* Using a more efficient regex syntax, such as `\b` instead of `\.` for word boundaries
* Using a library like `jsregex` for more advanced regex features
* Using a parsing library like `js-parser` to parse the string and perform operations on it

Keep in mind that the choice of approach depends on the specific use case, performance requirements, and personal preference.

Latest run results:

Run details: (Test run date: 3 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.16; rv:86.0) Gecko/20100101 Firefox/86.0

Browser/OS: Firefox 86 on Mac OS X 10.16

View result in a separate tab

Test name	Executions per second
if	15583349.0 Ops/sec
regex	18713178.0 Ops/sec
rexex2	18219480.0 Ops/sec
regex3	10818873.0 Ops/sec

Related benchmarks:

3xif||regexp (version: 0)

Comparing performance of: if vs regex vs rexex2 vs regex3

Created: 3 years ago by: Guest

Jump to the latest result

if

regex

rexex2

regex3

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 28 days ago):