Benchmark: stripped down reduce vs map + join

Script Preparation code:

var strings = {};
for (var i=0; i<1000; i++) {
  strings[i] = ""+i+i;
}
var keys = Object.keys(strings);

Tests:

for
var result = ""; for (var i in keys) { result += i; }
reduce
var result = keys.reduce(function(string, i) { return string+i; }, "");
map
var result = keys.map(function(i) { return i; }).join('');

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
for
reduce
map

Fastest: N/A

Slowest: N/A

Latest run results:

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

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**Benchmark Overview**

The provided benchmark measures the performance of three different approaches to concatenate numbers in JavaScript: a traditional `for` loop, the `reduce()` method, and the `map()` method with subsequent concatenation using the `join()` method.

**Approaches Compared**

1. **Traditional For Loop**: This approach uses a explicit `for` loop to iterate over an array of numbers and concatenate each number to a result string.
2. **Reduce() Method**: The `reduce()` method is a part of the Array.prototype object in JavaScript, which applies a function to each element of an array (in this case, concatenating numbers to a result string).
3. **Map() + Join() Method**: This approach uses the `map()` method to create an array of strings (by converting each number to a string), and then concatenates these strings using the `join()` method.

**Pros and Cons**

* **Traditional For Loop**:
	+ Pros: Easy to understand, no additional libraries or methods needed.
	+ Cons: Can be slow due to explicit looping, may not take advantage of optimizations in modern JavaScript engines.
* **Reduce() Method**:
	+ Pros: Efficient, optimized for performance by the browser engine.
	+ Cons: May require a good understanding of the `reduce()` method's behavior and its use case.
* **Map() + Join() Method**:
	+ Pros: Often faster than traditional loops or `reduce()` due to the optimization of concatenation in modern browsers.
	+ Cons: Requires an additional function call (using `map()`), which may incur some overhead.

**Library Usage**

None. This benchmark does not rely on any external libraries.

**Special JavaScript Features/Syntax**

* None mentioned, but note that this benchmark uses ES5 syntax (e.g., `for`, `Object.keys()`) and modern browser-specific optimizations (e.g., `map()` with concatenation).

**Alternative Approaches**

1. **Arrow Functions**: Instead of using the traditional `function` keyword for the reduction function in the `reduce()` method, arrow functions (`=>`) could be used.
2. **Array.prototype.forEach()**: Another approach to iterating over an array is by using the `forEach()` method, which does not require explicit looping or indexing.

**Considerations**

* Performance optimization techniques should always consider the specific use case and requirements of the application.
* The choice between different approaches may also depend on factors such as code readability, maintainability, and compatibility with older browsers.

Related benchmarks:

stripped down reduce vs map + join (version: 0)

Comparing performance of: for vs reduce vs map

Created: 3 years ago by: Guest

Jump to the latest result

for

reduce

map

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

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