Benchmark: delete vs check with 'in' before

Tests:

delete props
let obj = { prop1: 42 }; delete obj.prop1 delete obj.prop2 delete obj.prop3 delete obj.prop4
delete prop and check before
let obj = { prop1: 42 }; if ('prop1' in obj) { delete obj.prop1 } if ('prop2' in obj) { delete obj.prop2 } if ('prop3' in obj) { delete obj.prop3 } if ('prop4' in obj) { delete obj.prop4 }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
delete props
delete prop and check before

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):

LLMs can make mistakes. Check important info.

Let's dive into the provided benchmarking test cases on MeasureThat.net.

**Benchmark Description**

The benchmark measures the performance difference between two approaches: using `delete` statements with no checks (`"delete props"`), and using `delete` statements with checks using the `in` operator (`"delete prop and check before"`).

**Options Compared**

In the first approach, `"delete props"`, only `delete` statements are used without any checks. This means that if a property is not present in the object, the `delete` statement will have no effect.

In the second approach, `"delete prop and check before"`, both `delete` statements and checks using the `in` operator are used. The `in` operator allows checking if a property exists in the object before attempting to delete it.

**Pros and Cons of Each Approach**

1. **"delete props"**: This approach is simpler and more straightforward, as it only involves deleting properties without any checks. However, this can lead to better performance for browsers that optimize away unnecessary deletions.
2. **"delete prop and check before"**: This approach provides a safety net by checking if a property exists in the object before attempting to delete it. This prevents potential errors that might occur when trying to delete non-existent properties. However, this approach can lead to slightly worse performance due to the additional checks.

**Library Used**

There is no explicit library mentioned in the provided benchmarking test cases. It's likely that the benchmark uses built-in JavaScript functionality for these tests.

**Special JS Feature or Syntax**

The `in` operator used in the second approach is a standard feature of JavaScript, allowing developers to check if a property exists in an object.

**Other Alternatives**

If you're interested in exploring alternative approaches, here are a few options:

1. **Using `Object.prototype.hasOwnProperty.call()`**: Instead of using `in`, this method checks if a property is defined on the object's prototype chain and its own properties.
2. **Using `Object.hasOwn()`**: This method is similar to `in` but only checks the object's own properties, not its prototype chain.
3. **Using `try-catch` blocks with `delete`**: Instead of using `in`, you could use a `try-catch` block to attempt to delete a property and catch any errors that occur if the property doesn't exist.

Keep in mind that these alternatives might have different performance characteristics and may not be suitable for all use cases.

Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36

Browser/OS: Chrome 97 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
delete props	6984238.5 Ops/sec
delete prop and check before	12996340.0 Ops/sec

Related benchmarks:

delete vs check with 'in' before (version: 0)

Comparing performance of: delete props vs delete prop and check before

Created: 2 years ago by: Guest

Jump to the latest result

delete props

delete prop and check before

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):