Benchmark: String concatenation vs array join (w/ input)

Script Preparation code:

var str = "";
var i;
var sArr = [];

Tests:

String concatentation
for (i = 10; i > 0; i--) { str += "String concatenation. "; }
Array join
for (i = 10; i > 0; i--) { sArr[i] = "String concatenation. "; } str = sArr.join("");
Array join (w/ input)
for (i = 10; 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/ input)

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/605.1.15 (KHTML, like Gecko) Version/16.6.1 Safari/605.1.15

Browser/OS: Safari 16 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
String concatentation	500651.6 Ops/sec
Array join	644466.4 Ops/sec
Array join (w/ input)	919.0 Ops/sec

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

LLMs can make mistakes. Check important info.

**Overview of the Benchmark**

The provided JSON represents a JavaScript microbenchmark test case on MeasureThat.net. The benchmark compares three approaches for string concatenation: using `+` operator, array join, and modifying an existing array.

**Approaches Compared**

1. **String Concatenation (using + operator)**: This approach uses the `+` operator to concatenate strings.
2. **Array Join**: This approach creates an array of strings and then joins them using the `join()` method.
3. **Array Manipulation (with input)**: This approach modifies an existing array by pushing new strings onto it and then joins the modified array using the `join()` method.

**Pros and Cons of Each Approach**

1. **String Concatenation (using + operator)**
	* Pros:
		+ Simple to implement
		+ Fast execution time due to caching of intermediate results
	* Cons:
		+ Can lead to stack overflows for large inputs
2. **Array Join**
	* Pros:
		+ Can handle large inputs without worrying about stack overflows
	* Cons:
		+ Requires extra memory to store the array
3. **Array Manipulation (with input)**
	* Pros:
		+ Handles large inputs efficiently
	* Cons:
		+ May have slower execution time due to multiple push operations

**Library Used**

The `join()` method used in the Array Join approach is a built-in JavaScript function that concatenates all elements of an array into a single string.

**Special JS Feature/Syntax**

None mentioned in this benchmark.

**Other Considerations**

* The benchmark assumes that the input strings are constant and known beforehand.
* The benchmark measures the execution time per second, which may not accurately reflect performance in real-world scenarios where inputs vary.

**Alternatives**

If you're looking for alternative approaches to string concatenation or array manipulation, consider:

1. **Template literals**: A newer JavaScript syntax that allows efficient string interpolation using template literals (``${expression}``).
2. **String methods (e.g., `concat()`, `slice()`)**: Depending on the specific use case, these methods might be more efficient than traditional concatenation.
3. **Low-level optimizations**: For performance-critical code, consider using low-level optimization techniques like bit manipulation or SIMD instructions.

In general, when choosing an approach for string concatenation or array manipulation, consider factors such as:

* Input size and variability
* Memory constraints
* Performance requirements
* Code readability and maintainability

Related benchmarks:

String concatenation vs array join (w/ input) (version: 0)

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

Created: one year ago by: Guest

Jump to the latest result

String concatentation

Array join

Array join (w/ input)

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):