Benchmark: reverse string2 - MeasureThat.net

Script Preparation code:

var testcases = Array(1000).fill(0).map(() => Array(1000).fill(0).map(() => Math.floor(Math.random() * 10).toString()).join(""));

Tests:

split reverse join
for (let n = 0; n < 1000; n++) { const testcase = testcases[n]; const result = testcase.split("").reverse().join(""); }
traditional for loop
for (let n = 0; n < 1000; n++) { const testcase = testcases[n]; let result = ""; for (let i = testcase.length - 1; i >= 0; i--) { result += testcase[i]; } }
for of
for (let n = 0; n < 1000; n++) { const testcase = testcases[n]; let result = ""; for (const c of testcase) { result = c + result; } }
traditional for loop and join
for (let n = 0; n < 1000; n++) { const testcase = testcases[n]; let resultArr = []; for (let i = testcase.length - 1; i >= 0; i--) { resultArr.push(testcase[i]); } const result = resultArr.join(""); }
spread reverse join
for (let n = 0; n < 1000; n++) { const testcase = testcases[n]; const result = [...testcase].reverse().join(""); }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
split reverse join
traditional for loop
for of
traditional for loop and join
spread reverse join

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/101.0.0.0 Safari/537.36

Browser/OS: Chrome 101 on Windows

View result in a separate tab

Test name	Executions per second
split reverse join	63.6 Ops/sec
traditional for loop	223.6 Ops/sec
for of	163.2 Ops/sec
traditional for loop and join	51.8 Ops/sec
spread reverse join	52.3 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript benchmarks.

**What is being tested?**

The provided benchmark definition measures the performance of reversing a string in JavaScript using different approaches. The test cases are:

1. `split reverse join`: Uses the `split()`, `reverse()`, and `join()` methods to reverse a string.
2. `traditional for loop`: Uses a traditional for loop to iterate over the characters in the string, appending them to a result variable in reverse order.
3. `for of`: Uses the `for...of` loop to iterate over the characters in the string, concatenating them to a result variable in reverse order.
4. `traditional for loop and join`: Similar to the first approach, but uses the `join()` method to concatenate the reversed characters into a single string.
5. `spread reverse join`: Uses the spread operator (`...`) to create an array of characters, reversing it using the `reverse()` method, and then joining them back into a string.

**Options compared:**

Each test case presents a different approach to reversing a string in JavaScript. The main differences are:

* **Iterative vs. Declarative**: Approaches 1, 2, and 3 use iterative methods (for loops), while approaches 4 and 5 use declarative methods (using `join()` or the spread operator).
* **String manipulation vs. Array manipulation**: Approach 1 uses string manipulation, while approaches 4 and 5 use array manipulation.
* **Performance overhead**: Approaches with more function calls or data structure creations (e.g., approach 2) may incur additional performance overhead.

**Pros and Cons:**

Here are some general pros and cons of each approach:

* **Split reverse join**:
	+ Pros: Easy to implement, widely supported.
	+ Cons: May be slower due to the creation of intermediate arrays or strings.
* **Traditional for loop**:
	+ Pros: Control over iteration order, can avoid unnecessary string creation.
	+ Cons: More verbose, may require more memory allocation.
* **For of**:
	+ Pros: Elegant, concise syntax, suitable for many use cases.
	+ Cons: May not be as efficient as traditional loops due to overhead from the iterator object.
* **Traditional for loop and join**:
	+ Similar pros and cons to approach 1.
* **Spread reverse join**:
	+ Pros: Modern, concise syntax, avoids unnecessary string creation.
	+ Cons: May require additional memory allocation due to the spread operator.

**Library usage**

None of the provided test cases use any external libraries. They are all standard JavaScript implementation.

**Special JS features or syntax**

The only special feature used in these test cases is the `for...of` loop, which was introduced in ECMAScript 2015 (ES6).

**Other alternatives**

If you're interested in exploring other approaches, here are a few more options:

* **Reduce()**: Use the `reduce()` method to accumulate the characters into a single string.
* **Array.prototype.map()`: Use the `map()` method to create a new array of reversed characters and then join them using the `join()` method.
* **Regexp**: Use regular expressions to reverse a string (though this is generally considered less efficient).

These alternatives may offer different trade-offs in terms of performance, readability, or code complexity.

Related benchmarks:

reverse string2 (version: 1)

Comparing performance of: split reverse join vs traditional for loop vs for of vs traditional for loop and join vs spread reverse join

Created: 3 years ago by: Registered User

Jump to the latest result

split reverse join

traditional for loop

for of

traditional for loop and join

spread reverse join

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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