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stringbuilder
(version: 0)
Comparing performance of:
join vs concatenate
Created:
2 years ago
by:
Guest
Go to the latest result
Tests:
join
const arr = [] for (let i=0; i<100000; i++) { arr.push('a' + i) } console.log(arr.join(''))
concatenate
let b = '' for (let i=0; i<100000; i++) { b += 'a' + i } console.log(b)
Rendered benchmark preparation results:
Suite status:
<idle, ready to run>
Run tests (2)
Previous results
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Test case name
Result
join
concatenate
Fastest:
N/A
Slowest:
N/A
Latest run results:
Run details:
(Test run date:
2 years ago
)
User agent:
Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/17.0 Safari/605.1.15
Browser/OS:
Safari 17 on Linux
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<iframe src="https://measurethat.net/Embed?id=534082" width="100%" height="500px"></iframe>
concatenate
22/s
join
12/s
View exact numbers
Test name
Executions per second
✓
concatenate
22 Ops/sec
join
12 Ops/sec
Autogenerated LLM Summary
(model
llama3.2:3b
, generated one year ago):
Let's break down the provided benchmarking test cases and explain what's being tested, compared, and the pros/cons of each approach. **Benchmark Definition** The JSON object representing the benchmark contains the following properties: * `Name`: The name of the benchmark, which is "stringbuilder". * `Description`: An empty string, indicating that no description is provided for this benchmark. * `Script Preparation Code` and `Html Preparation Code`: Empty strings, suggesting that no script or HTML preparation code needs to be executed before running the benchmark. **Individual Test Cases** The benchmark consists of two individual test cases: 1. **"join"`** ```javascript const arr = [] for (let i=0; i<100000; i++) { arr.push('a' + i) } console.log(arr.join('')) ``` This test case creates an array `arr` with 100,000 elements and then logs the result of calling the `join()` method on the array, concatenating all elements with a space separator. 2. **"concatenate"`** ```javascript let b = '' for (let i=0; i<100000; i++) { b += 'a' + i } console.log(b) ``` This test case creates an empty string `b` and then appends 100,000 elements to it using the `+=` operator. **Comparison of Approaches** Both approaches aim to measure the performance of concatenating strings in JavaScript. However, they differ in their approach: * **"join()"**: This method uses a built-in array method that iterates over the elements and appends them to an internal buffer. The resulting string is then returned. * **"concatenate"`: This approach uses a simple loop to append elements to a string. **Pros and Cons** **"join()"**: Pros: * Efficient, as it uses optimized code in the browser's engine. * Less memory-intensive, as it doesn't require creating an array of strings. Cons: * May not be suitable for small arrays or strings, where the overhead of `join()` may outweigh the benefits. * Can result in a larger final string if the elements are longer than the space separator. **"concatenate"`: Pros: * Simple and easy to understand. * Suitable for small arrays or strings. Cons: * Less efficient due to the loop and string concatenation, which can lead to slow performance. * Memory-intensive, as it creates a new array of strings in memory. **Library: `join()`** The `join()` method is a built-in JavaScript function that concatenates elements from an array into a single string. It's optimized for performance and uses internal buffers to minimize overhead. **Special JS Feature/Syntax** This benchmark doesn't utilize any special JavaScript features or syntax, making it accessible to developers with varying levels of expertise. **Alternatives** If you're looking for alternative approaches or have specific requirements, consider the following: 1. **Use a different string concatenation method**: You could use `Array.prototype.map()` and `Array.prototype.join()`, which can be more efficient for large arrays. 2. **Use a library like Lodash**: Lodash provides an optimized `join()` function that can be used instead of the built-in one. 3. **Optimize for small strings**: If you're working with very short strings, you might consider using a simpler approach like string concatenation or even using a fixed-width string format to reduce overhead. Keep in mind that benchmarking JavaScript performance can be complex and dependent on various factors, such as the browser engine, platform, and hardware.
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