Benchmark: String concatenation vs array join [previous author fucked up]

Script Preparation code:

var str = "";
var i;

Tests:

String concatentation
var sArr = []; for (i = 1000; i > 0; i--) { str += "String concatenation. "; }
Array join
var sArr = []; for (i = 1000; i > 0; i--) { sArr[i] = "String concatenation. "; } str = sArr.join("");
Array join (w/ push)
var sArr = []; for (i = 1000; i > 0; i--) { sArr.push("String concatenation. "); } str = sArr.join("");

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
String concatentation
Array join
Array join (w/ push)

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/114.0.0.0 Safari/537.36

Browser/OS: Chrome 114 on Linux

View result in a separate tab

Test name	Executions per second
String concatentation	1523.1 Ops/sec
Array join	22435.3 Ops/sec
Array join (w/ push)	16088.7 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark.

**Benchmark Definition:**
The benchmark measures the performance difference between three approaches for string concatenation:

1. **String Concatenation**: Directly appending strings to a variable using the `+` operator.
2. **Array Join**: Using an array and the `join()` method to concatenate all elements into a single string.
3. **Array Join with Push**: Using an array, pushing individual strings onto it, and then joining them together.

**Options Compared:**

* String concatenation (directly using `+`)
* Array join (using `join()` on an array)
* Array join with push (pushing individual strings onto an array before joining)

**Pros and Cons of Each Approach:**

1. **String Concatenation**
	* Pros: Simple, straightforward, and easy to understand.
	* Cons: Can lead to inefficient memory allocation and copying of intermediate results.
2. **Array Join**
	* Pros: More efficient than string concatenation, as it avoids intermediate allocations.
	* Cons: May incur a higher overhead due to the `join()` method, which can create an additional array and copy its elements.
3. **Array Join with Push**
	* Pros: Offers a balance between efficiency and simplicity, as it combines the benefits of both approaches.
	* Cons: Requires pushing individual strings onto an array, which may be slower than using `join()` directly.

**Library/External Dependencies:**
There are no external libraries mentioned in the benchmark definition. The only library used is JavaScript's built-in `Array` and string manipulation functions.

**Special JS Features/Syntax:**
The benchmark uses JavaScript's variable `i`, which represents a counter, but it doesn't use any advanced features like async/await or generator functions.

**Alternative Approaches:**

* **Using template literals:** Another approach to string concatenation is using template literals (e.g., `str += `${someString}`;`). This method avoids the need for explicit concatenation and can be more efficient.
* **Using a string buffer library:** For large-scale string concatenation, specialized libraries like buffers or streams can provide better performance by avoiding intermediate allocations.

Keep in mind that these alternative approaches might not be directly relevant to the specific benchmark being measured.

Related benchmarks:

String concatenation vs array join [previous author fucked up] (version: 0)

Comparing performance of: String concatentation vs Array join vs Array join (w/ push)

Created: one year ago by: Guest

Jump to the latest result

String concatentation

Array join

Array join (w/ push)

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):