Benchmark: delete vs undefined vs null

Script Preparation code:

test = {
    test: {
        hello: 'your mom'
    }
}

Tests:

delete
delete test.test.hello
undefined
test.test.hello = undefined
null
test.test.hello = null

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
delete
undefined
null

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 3 years ago)

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/90.0.4430.212 Safari/537.36

Browser/OS: Chrome 90 on Linux

View result in a separate tab

Test name	Executions per second
delete	3090481.0 Ops/sec
undefined	2270050.5 Ops/sec
null	4446899.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks.

**What is being tested?**

The provided JSON represents a benchmark test that compares the performance of three different approaches to delete a property from an object in JavaScript:

1. **Delete**: `delete test.test.hello`
2. **Undefined**: `test.test.hello = undefined`
3. **Null**: `test.test.hello = null`

**Options compared**

The benchmark is comparing the performance of these three approaches, which involve removing the property "hello" from the object `test`.

* **Delete**: This approach uses the `delete` keyword to remove the property from the object.
* **Undefined**: This approach assigns `undefined` to the property, effectively removing it from the object.
* **Null**: This approach assigns `null` to the property, also effectively removing it from the object.

**Pros and Cons of each approach**

1. **Delete**:
	* Pros: Simple, straightforward, and efficient way to remove a property.
	* Cons: May not work as expected if the property is accessed after deletion (e.g., `if ('hello' in test)`).
2. **Undefined**:
	* Pros: Similar performance to delete, but may be more readable for some developers.
	* Cons: Assigning `undefined` can lead to unexpected behavior if used in certain contexts (e.g., `test.test.hello === undefined` will always be false).
3. **Null**:
	* Pros: Simple and efficient way to remove a property, similar to delete.
	* Cons: May not work as expected if the property is accessed after deletion (e.g., `if ('hello' in test)`).

**Library usage**

None of the benchmark cases use any external libraries.

**Special JS feature or syntax**

There are no special JavaScript features or syntax used in this benchmark. All three approaches rely on standard JavaScript syntax.

**Other alternatives**

In addition to these three approaches, there may be other ways to remove a property from an object in JavaScript, such as:

* Using the `Object.keys()` and `splice()` methods to remove a property by its key.
* Using a library like Lodash or underscore.js to manipulate objects.

However, these alternative approaches are not included in this benchmark.

In summary, the benchmark is designed to compare the performance of three simple yet effective ways to remove a property from an object in JavaScript. The results will help developers understand which approach is most efficient and suitable for their use cases.

Related benchmarks:

delete vs undefined vs null (version: 0)

Comparing performance of: delete vs undefined vs null

Created: 4 years ago by: Guest

Jump to the latest result

delete

undefined

null

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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