Benchmark: reduce with spread

Tests:

reduce with spread
const arr = [ { id: "ironman", name: "Tony Stark" }, { id: "hulk", name: "Bruce Banner" }, { id: "blackwidow", name: "Natasha Romanoff" }, ]; const superheroes1 = arr.reduce( (acc, item) => ({ ...acc, [item.id]: [item.name], }), {} );
foreach
const arr = [ { id: "ironman", name: "Tony Stark" }, { id: "hulk", name: "Bruce Banner" }, { id: "blackwidow", name: "Natasha Romanoff" }, ]; const superheroes2 = {}; arr.forEach((o) => (superheroes2[o.id] = o.name));

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
reduce with spread
foreach

Fastest: N/A

Slowest: N/A

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

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**Benchmark Explanation**

MeasureThat.net is a website that allows users to create and run JavaScript microbenchmarks. The provided JSON represents two benchmark definitions:

1. **"reduce with spread"`: This benchmark tests the performance of using the spread operator (`...`) in combination with `Array.prototype.reduce()` to process an array of objects.
2. **"foreach"`: This benchmark tests the performance of using a traditional `forEach` loop to process an array of objects.

**Options Compared**

The two benchmarks compare different approaches to achieve the same result:

* In the "reduce with spread" benchmark, the JavaScript code uses `Array.prototype.reduce()` in combination with the spread operator (`...`) to create a new object.
* In the "foreach" benchmark, the JavaScript code uses a traditional `forEach` loop to iterate over the array of objects and assign values to an empty object.

**Pros and Cons**

Here's a brief analysis of each approach:

1. **"reduce with spread"`:
	* Pros:
		+ More concise and expressive code.
		+ Can be more efficient in terms of memory usage, as it avoids creating unnecessary intermediate arrays.
	* Cons:
		+ May have higher overhead due to the use of `Array.prototype.reduce()` and spread operator.
		+ Can lead to slower performance if not optimized correctly.
2. **"foreach"`:
	* Pros:
		+ Often easier to read and understand, especially for developers without experience with functional programming concepts.
	* Cons:
		+ Can result in slower performance due to the overhead of creating an intermediate array (in this case, an empty object).
		+ May require more code and manual memory management.

**Libraries and Special JS Features**

Neither benchmark uses any external libraries or special JavaScript features. However, it's worth noting that `Array.prototype.reduce()` is a built-in method in modern JavaScript, which makes the "reduce with spread" benchmark particularly relevant to developers familiar with functional programming concepts.

**Alternative Approaches**

Other approaches to achieve the same result as these two benchmarks could include:

* Using a traditional `for` loop or `while` loop to iterate over the array of objects.
* Using a library like Lodash, which provides utility functions for working with arrays and objects.
* Implementing a custom mapping function using recursion or iteration.

**Additional Considerations**

When writing JavaScript code for performance-critical applications, it's essential to consider factors such as:

* Memory usage and allocation
* Cache locality and coherence
* CPU pipeline utilization and instruction-level parallelism
* Garbage collection overhead and frequency

By understanding the trade-offs between different approaches and optimizing code for specific use cases, developers can write more efficient JavaScript code that takes full advantage of modern hardware and libraries.

Related benchmarks:

reduce with spread (version: 0)

Comparing performance of: reduce with spread vs foreach

Created: 3 years ago by: Registered User

Jump to the latest result

reduce with spread

foreach

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):