Benchmark: Replace with regex or replace

Script Preparation code:

var css = `@charset "UTF-8";

.dx-validationsummary-item-content {
  border-bottom: 1px dashed;
  display: inline-block;
  line-height: normal;
}
@-webkit-keyframes valid-badge-frames {
  from {
    opacity: 0;
    -webkit-transform: scale(.1);
    transform: scale(.1);
  }
  to {
    opacity: 1;
    -webkit-transform: scale(1);
    transform: scale(1);
  }
}`;

var header = '/** created by devexpress \n version: 1.1.1\n copyright\n*/';
var result = '';

Tests:

regex
result = css.replace(/^(@charset "UTF-8";\n)?([\S\s]*)/, `$1${header}$2`);
replace
if (css.startsWith('@charset "UTF-8";')) { result = `@charset "UTF-8";\n${header}${css.replace('@charset "UTF-8";\n', '')}`; } else { result = header + css; }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
regex
replace

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Linux; arm_64; Android 12; M2101K6G) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/104.0.5112.114 YaBrowser/22.9.4.79.00 SA/3 Mobile Safari/537.36

Browser/OS: Yandex Browser 22 on Android

View result in a separate tab

Test name	Executions per second
regex	452483.3 Ops/sec
replace	961190.1 Ops/sec

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

LLMs can make mistakes. Check important info.

I'll break down the provided JSON and explain what's being tested.

**Benchmark Definition**

The benchmark definition is a set of instructions that outlines how to prepare the test data and execute the test. In this case, there are two options:

1. **Regex (Regular Expression) Approach**: This approach uses the `replace()` method with a regular expression to match and replace the specified string.
2. **Replace Approach**: This approach uses an if-else statement to check if the CSS string starts with the specified string, and then replaces or appends it accordingly.

**Options Compared**

The two approaches being compared are:

* Regex (Regular Expression) Approach:
	+ Pros: Can be more concise and efficient for simple replacements.
	+ Cons: May be slower for complex patterns or large datasets.
* Replace Approach:
	+ Pros: Can be more readable and maintainable, especially for complex logic.
	+ Cons: May be slower due to the overhead of conditional checks.

**Library Usage**

There is no explicit library usage mentioned in the benchmark definition. However, the `replace()` method is a built-in JavaScript function that can be used without any external libraries.

**Special JS Features or Syntax**

There are no special JavaScript features or syntax being tested in this benchmark. The instructions are straightforward and do not involve advanced concepts like async/await, callbacks, or closures.

**Other Alternatives**

If the Regex approach were not available, alternative solutions could include:

* Using a string manipulation library like `lodash` or `string-prompt`.
* Implementing a custom replacement logic using JavaScript's built-in string methods.
* Using a templating engine like Handlebars to generate the replaced CSS string.

In the Replace approach, if the `startsWith()` method were not available, alternative solutions could include:

* Using an if-else statement with `indexOf()` or `match()` methods instead.
* Implementing a custom logic using JavaScript's built-in conditional statements.
* Using a library like `regex` for regular expression matching.

In summary, the benchmark is comparing two approaches to replace a string in CSS: one using regex and the other using an if-else statement. The choice of approach depends on the specific requirements and performance considerations.

Related benchmarks:

Replace with regex or replace (version: 0)

Comparing performance of: regex vs replace

Created: 4 years ago by: Guest

Jump to the latest result

regex

replace

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):