Benchmark: regex Vs. for loop

Tests:

for loop
const format = 'MM/DD/YYYY'; const inputs = ['0', '1', '0', '3', '2','0','0' ] const dateTxtArray = []; const formatArray = Array.from(format); for (let i = 0; i < formatArray.length; i++) { if (formatArray[i] === '/') { dateTxtArray.push(formatArray.splice(i, 1)[0] ?? ''); } dateTxtArray.push(inputs[i] ?? formatArray[i] ?? ''); } const dateTxt = dateTxtArray.join(''); return dateTxt;
regex
const format = 'MM/DD/YYYY'; const inputs = ['0', '1', '0', '3', '2','0','0' ] myInputs = inputs.join("").replace(/^(\d{2})/g, '$1/').replace(/^(\d{2}\/\d{2})/g, '$1/'); return myInputs + format.substr(myInputs.length);

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: one year ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/114.0.0.0 Safari/537.36

Browser/OS: Chrome 114 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
for loop	3033220.2 Ops/sec
regex	2172305.8 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 benchmark and explain what's being tested, compared, and the pros and cons of each approach.

**What's being tested:**

The benchmark is comparing two approaches to format dates in a specific way:

1. **For Loop**: The first test case uses a traditional `for` loop to iterate through the date components (MM, DD, YYYY) and concatenate them with the input values.
2. **Regular Expression (Regex)**: The second test case uses a regex pattern to achieve the same result.

**Options compared:**

* For Loop vs. Regex
* Both approaches are used to format dates in the following way: MM/DD/YYYY

**Pros and Cons of each approach:**

1. **For Loop**:
	* Pros:
		+ Easy to understand and implement for developers familiar with loops.
		+ Can be optimized further by using techniques like caching or memoization.
	* Cons:
		+ May not be as efficient as regex, especially for large input datasets.
		+ More code to write, which can increase the risk of errors.
2. **Regex**:
	* Pros:
		+ Highly optimized and efficient, making it suitable for high-performance applications.
		+ Can handle complex formatting scenarios with ease.
	* Cons:
		+ Steeper learning curve due to its unique syntax and patterns.
		+ May be harder to debug and maintain.

**Library used:**

There is no specific library mentioned in the benchmark definition, but regex patterns are often included using built-in JavaScript functions like `replace()` or by importing external libraries like `regex-patterns`.

**Special JS features/syntax:**

* The use of template literals (`''`) for string interpolation and concatenation.
* The use of the spread operator (`...`) to expand arrays.

**Other considerations:**

* **Benchmarking**: The benchmark measures the execution speed of each approach, which is essential for performance-critical applications.
* **Consistency**: The benchmark ensures that both approaches produce identical results, making it easier to compare and analyze their performance.
* **Device-specific optimizations**: The test accounts for variations in device platforms (e.g., Desktop vs. Mobile) and operating systems.

**Alternatives:**

Other alternatives could be:

* Using a date formatting library like `moment.js` or `date-fns`, which provides more advanced formatting options and can reduce the complexity of implementing custom formatting logic.
* Implementing the formatting logic using other programming paradigms, such as functional programming or assembly languages (although these might not be practical for JavaScript development).
* Using a different approach entirely, like using a parser generator tool to create a parsing algorithm from an abstract syntax tree.

Related benchmarks:

regex Vs. for loop (version: 0)

compare regex vs for looop

Comparing performance of: for loop vs regex

Created: one year ago by: Registered User

Jump to the latest result

for loop

regex

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):