Benchmark: Object.fromEntries x reduce (correctly using fromEntries)

Script Preparation code:

var data = { ...Array.from(Array(10000).keys()) };

Tests:

Object.fromEntries
Object.fromEntries(Object.entries(data));
Reduce (reuse object)
Object.entries(data).reduce((acc, [k, v]) => { acc[k] = v; return acc; }, {});
Reduce (creating temporary objects)
Object.entries(data).reduce((acc, [k, v]) => ({ ...acc, [k]: v }), {});

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Object.fromEntries
Reduce (reuse object)
Reduce (creating temporary objects)

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/105.0.0.0 Safari/537.36

Browser/OS: Chrome 105 on Windows

View result in a separate tab

Test name	Executions per second
Object.fromEntries	866.9 Ops/sec
Reduce (reuse object)	1529.5 Ops/sec
Reduce (creating temporary objects)	46.0 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 benchmark.

**Benchmark Definition JSON**

The provided JSON defines a benchmark test that involves creating an object from an array of key-value pairs using two different methods: `Object.fromEntries` and `reduce`. The benchmark measures the performance difference between these two approaches.

Here's what we're testing:

1. **Object.fromEntries**: This method creates an object by passing an iterable (in this case, an array) of key-value pairs to the constructor.
2. **Reduce (reuse object)**: This approach uses the `reduce` method to iterate over the array and create a new object by assigning values to existing keys or creating new ones.
3. **Reduce (creating temporary objects)**: This approach is similar to the previous one, but it creates temporary objects instead of reusing an existing one.

**Options Compared**

We're comparing three options:

1. `Object.fromEntries`
2. `reduce` with reuse
3. `reduce` without reuse

These options are compared in terms of performance.

**Pros and Cons of Each Approach**

Here's a brief summary of the pros and cons of each approach:

1. **Object.fromEntries**:
	* Pros: Simple, concise syntax; can be faster for small to medium-sized datasets.
	* Cons: May have performance issues with large datasets due to its overhead.
2. **Reduce (reuse object)**:
	* Pros: Can be more efficient than `Object.fromEntries` for large datasets, as it avoids the overhead of creating a new object.
	* Cons: Requires more code and can be less readable; may cause issues if not used correctly.
3. **Reduce (creating temporary objects)**:
	* Pros: Similar to `reduce (reuse object)`, but with an additional overhead due to temporary object creation.
	* Cons: May have performance implications similar to the first approach.

**Library Usage**

There's no explicit library usage in this benchmark, as it only involves built-in JavaScript methods.

**Special JS Features or Syntax**

The benchmark uses the `reduce` method, which is a special syntax introduced in ECMAScript 2015. It allows for more concise code and improved performance compared to traditional loop constructs.

**Other Considerations**

When using these approaches, consider the following:

* For small datasets, `Object.fromEntries` may be a better choice due to its simplicity.
* For large datasets, `reduce (reuse object)` or `reduce (creating temporary objects)` might be more efficient.
* Be mindful of performance implications and potential issues with the `reduce` method.

**Alternatives**

If you're looking for alternative approaches, consider:

1. Using a library like Lodash to simplify your code and improve performance.
2. Implementing a custom loop construct instead of using the `reduce` method.
3. Using other methods, such as `Array.prototype.reduce.call()` or `Array.prototype.forEach()`, which may offer different trade-offs in terms of performance and readability.

Keep in mind that these alternatives might not be directly comparable to the original benchmark, as they would require modifications to the test code.

Related benchmarks:

Object.fromEntries x reduce (correctly using fromEntries) (version: 0)

Comparing performance of: Object.fromEntries vs Reduce (reuse object) vs Reduce (creating temporary objects)

Created: 2 years ago by: Guest

Jump to the latest result

Object.fromEntries

Reduce (reuse object)

Reduce (creating temporary objects)

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):