Benchmark: Delete property from object

Script Preparation code:

var person = {name: "neka", age: 1, status: 'A', married: false, owner: false };

Tests:

`delete` keyword
delete person.name; delete person.age; delete person.status; delete person.married;
Setting prop to `null`
person.name = null person.age = null person.status = null person.married = null

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
`delete` keyword
Setting prop to `null`

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one month ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.36

Browser/OS: Chrome 131 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
`delete` keyword	5241332.0 Ops/sec
Setting prop to `null`	5166297.5 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into explaining the benchmark and its different approaches.

**Benchmark Overview**

The benchmark measures the performance of two ways to remove properties from an object: using the `delete` keyword and setting a property to `null`. The test case creates an object with several properties, including `name`, `age`, `status`, `married`, and `owner`.

**Approaches Compared**

There are two approaches compared:

1. **Using `delete` keyword**: This approach uses the `delete` operator to remove properties from the object.
```javascript
delete person.name;
delete person.age;
delete person.status;
delete person.married;
```
2. **Setting prop to `null`**: This approach sets individual properties to `null` to effectively remove them from the object.
```javascript
person.name = null;
person.age = null;
person.status = null;
person.married = null;
```

**Pros and Cons of Each Approach**

1. **Using `delete` keyword**:
	* Pros:
		+ More concise and expressive syntax.
		+ Fewer memory allocations (since no new object is created).
	* Cons:
		+ May not work as expected in certain situations, such as when the property is accessed before being deleted.
		+ Can be slower due to the overhead of removing properties from the object's internal data structure.
2. **Setting prop to `null`**:
	* Pros:
		+ More predictable behavior (since setting a property to `null` will always remove it).
		+ May be faster due to the optimized performance of assigning `null` to properties.
	* Cons:
		+ Less concise and less expressive syntax.
		+ Involves more memory allocations (since new objects are created).

**Library Used**

In this benchmark, no libraries are explicitly mentioned. However, it's worth noting that in general, JavaScript engines have built-in optimizations for property removal, which can affect the performance of these two approaches.

**Special JS Feature/Syntax**

This benchmark does not use any special JavaScript features or syntax beyond basic JavaScript syntax. It only uses standard JavaScript operators and data structures.

**Other Alternatives**

There are a few alternative approaches that could be considered:

1. **Using `delete` on an array**: Since objects with arrays as properties can be more efficient to remove from, using `delete` on the array element might be faster.
2. **Using `Object.keys()` and `forEach()`**: This approach would involve iterating over the object's property names using `Object.keys()` and then removing each property using a callback function.
3. **Using a library or framework-specific optimization**: Depending on the specific library or framework being used, there might be optimized methods for removing properties from objects that could affect performance.

Overall, this benchmark provides a good representation of the trade-offs between these two approaches and can help developers understand the implications of choosing one over the other in their own code.

Related benchmarks:

Delete property from object (version: 2)

Testing the performance of using `delete` keyword VS setting prop to null to remove an property of an object

Comparing performance of: `delete` keyword vs Setting prop to `null`

Created: 6 years ago by: Registered User

Jump to the latest result

`delete` keyword

Setting prop to `null`

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):