Benchmark: undefined vs delete

Tests:

delete
const obj = {one: "hello"} delete obj.one;
undefined
const obj = {one: "sunshine"} obj.one = undefined;

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
delete
undefined

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 27 days ago):

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark and explain what's being tested.

**Benchmark Definition**

The benchmark is designed to compare two approaches for setting a property on an object:

1. **delete**: This approach deletes the property from the object using the `delete` keyword.
2. **undefined**: This approach sets the property to `undefined` using the assignment operator (`=`) with no value.

**Options Being Compared**

The benchmark is comparing the performance of these two approaches across different browsers and devices. The test case uses JavaScript, which allows for various options and syntaxes.

**Pros and Cons of Each Approach:**

1. **delete**
	* Pros:
		+ Can be faster since it doesn't create a new property with an undefined value.
		+ May have better cache locality or memory efficiency.
	* Cons:
		+ May not work in all situations, such as when the object is frozen or has strict mode enabled.
		+ Can throw errors if the property does not exist.
2. **undefined**
	* Pros:
		+ Works in most situations, including when the object is frozen or has strict mode enabled.
		+ Does not throw errors even if the property does not exist.
	* Cons:
		+ May create a new property with an undefined value, which can affect performance and memory usage.

**Library**

In this benchmark, no libraries are explicitly mentioned. However, it's likely that the JavaScript engine being tested (e.g., V8 in Chrome) provides some built-in optimizations or implementations for these properties.

**Special JS Feature/Syntax**

The benchmark does not mention any special JavaScript features or syntaxes. The focus is on the basic property setting approach, which is a fundamental aspect of JavaScript.

**Other Alternatives**

If you're looking to create similar benchmarks, consider testing other aspects of object property setting, such as:

* Using `Object.defineProperty()` with different properties (e.g., writable, enumerable)
* Setting properties using `this` or `that`
* Comparing performance of different data structures for storing and retrieving values
* Testing the impact of various optimization techniques on property setting

For example, you could create benchmarks for testing the following scenarios:

* Property setting using `Object.defineProperty()`: Compare the performance of setting properties using `Object.defineProperty()` with different configuration options.
* Using `this` or `that`: Benchmark the performance of setting properties using `this` or `that` compared to assigning values directly.
* Data structure comparison: Test the performance of storing and retrieving values in different data structures, such as arrays, objects, or sets.

By exploring these alternatives, you can create more comprehensive benchmarks that provide insights into various aspects of JavaScript property setting.

Latest run results:

Run details: (Test run date: 4 years ago)

User agent: Mozilla/5.0 (iPhone; CPU iPhone OS 13_5 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) CriOS/83.0.4103.88 Mobile/15E148 Safari/604.1

Browser/OS: Chrome Mobile iOS 83 on iOS 13.5

View result in a separate tab

Test name	Executions per second
delete	23016822.0 Ops/sec
undefined	8165169.0 Ops/sec

Related benchmarks:

undefined vs delete (version: 0)

Comparing performance of: delete vs undefined

Created: 4 years ago by: Guest

Jump to the latest result

delete

undefined

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 27 days ago):