Benchmark: Object keys vs Object entires - ChangeHow

Script Preparation code:

data = {
    name: 'Mark',
    message: 'hello world'
}

Tests:

Object keys
const transcription = {}; Object.keys(data).forEach(key => transcription[key] = data[key]); return transcription;
Object entries
const transcription = {}; Object.entries(data).forEach(([key, value]) => transcription[key] = value); return transcription;

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Object keys
Object entries

Fastest: N/A

Slowest: N/A

Latest run results:

No previous run results

This benchmark does not have any results yet. Be the first one to run it!

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

LLMs can make mistakes. Check important info.

Let's break down the benchmark and its test cases.

**Benchmark Overview**

The "ChangeHow" benchmark is designed to compare two approaches for copying data from an object: using `Object.keys()` and `Object.entries()`. The benchmark provides a sample data object with string values, which is used as input for both test cases.

**Options Compared**

Two options are compared:

1. **Using `Object.keys()`**: This approach iterates over the object's key-value pairs using an array of keys.
2. **Using `Object.entries()`**: This approach iterates directly over the object's key-value pairs as an array of arrays, where each inner array contains a key and its corresponding value.

**Pros and Cons**

Here are some pros and cons of each approach:

* **Using `Object.keys()`:**
	+ Pros:
		- Can be faster for large objects since it doesn't create intermediate arrays.
		- More memory-efficient, as it only stores keys in memory.
	+ Cons:
		- Requires manual loop iteration, which can lead to less readable code.
		- May not be suitable for non-object iterables (e.g., arrays).
* **Using `Object.entries()`:**
	+ Pros:
		- More concise and readable code, as it avoids manual loop iteration.
		- Suitable for both objects and non-object iterables (e.g., arrays with custom entries).
	+ Cons:
		- May be slower due to the overhead of creating intermediate arrays.

**Library/External Functionality**

There is no external library or function used in this benchmark. However, it's worth noting that `Object.entries()` was introduced in ECMAScript 2015 (ES6), and its usage has become more common since then.

**Special JS Feature/Syntax**

The benchmark doesn't explicitly use any special JavaScript features or syntax. It only uses standard ES6 features like object literals, destructuring, and arrow functions.

**Other Considerations**

When choosing between `Object.keys()` and `Object.entries()`, consider the following:

* If you need to work with non-object iterables or require more control over the iteration process, `Object.entries()` might be a better choice.
* If memory efficiency is crucial and you're working with large objects, `Object.keys()` could provide a performance advantage.

**Alternative Approaches**

Other approaches for copying data from an object include:

1. Using the spread operator (`{...data}`) to create a new object literal.
2. Utilizing the `JSON.parse(JSON.stringify(data))` method (for more complex data structures).
3. Implementing a custom loop using `for...in` or `for...of` loops.

Keep in mind that these alternatives might have different performance characteristics, readability, and memory usage compared to `Object.keys()` and `Object.entries()`.

Related benchmarks:

Object keys vs Object entires - ChangeHow (version: 0)

Comparing performance of: Object keys vs Object entries

Created: 4 years ago by: Guest

Jump to the latest result

Object keys

Object entries

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):