Benchmark: omit function testing

Script Preparation code:

obj = { name: 'Frank', age: '12', 1: 1, 2: 2, 3: 3 }
keys = ['age', 1, 3]

Tests:

current
const newObj = {}; const keysToInclude = Object.keys(obj).filter(key => !keys.includes(key)); for (const key of keysToInclude) { newObj[key] = obj[key]; }
new
const result = {}; for (const [key, value] of Object.entries(obj)) { if (!keys.includes(key)) { result[key] = value; } }
new delete
newObj = { ...obj }; keys.forEach(key => delete newObj[key])
new delete (assign)
const newObj = Object.assign({}, obj) keys.forEach(key => delete newObj[key])
new delete (mutates)
keys.forEach(key => delete obj[key])

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
current
new
new delete
new delete (assign)
new delete (mutates)

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/112.0.0.0 Safari/537.36

Browser/OS: Chrome 112 on Windows

View result in a separate tab

Test name	Executions per second
current	197821.2 Ops/sec
new	261681.9 Ops/sec
new delete	359675.5 Ops/sec
new delete (assign)	203860.4 Ops/sec
new delete (mutates)	452194.2 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down the provided JSON and individual test cases to understand what is being tested, compared, and analyzed.

**Benchmark Context**

MeasureThat.net is a website that allows users to create and run JavaScript microbenchmarks. The goal is to compare the performance of different approaches for a specific problem or function.

**Test Case: Omit Function Testing**

The benchmark tests four different ways to omit certain keys from an object:

1. **New Delete (Mutates)**: `keys.forEach(key => delete obj[key])`
2. **New Delete (Assign)**: `const newObj = Object.assign({}, obj); keys.forEach(key => delete newObj[key])`
3. **Current**: This approach is not specified in the JSON, but it's mentioned in the test name.
4. **New**: This approach uses `Object.entries(obj)` and iterates over the entries to filter out unwanted keys.

**Options Compared**

The benchmark compares four different approaches:

*   `New Delete (Mutates)`: Directly deletes properties from the original object (`obj`).
*   `New Delete (Assign)`: Creates a new object by assigning an empty object to `Object.assign()`, and then deletes properties from this new object.
*   **Current**: This approach is not explicitly defined, but it's likely using some variation of the other approaches.

**Pros and Cons**

Here are some pros and cons of each approach:

*   **New Delete (Mutates)**:
    *   Pros: Efficient use of iteration and no need to create a new object.
    *   Cons: Modifies the original object, which might have performance implications for certain applications.
*   **New Delete (Assign)**:
    *   Pros: Creates a new object, which can be beneficial for immutability or performance in some cases.
    *   Cons: Requires an extra step and might incur additional overhead due to object creation.
*   **Current** (Assuming it's similar to `New`):
    *   Pros: Uses iteration and filtering, which can be efficient for large datasets.
    *   Cons: Might be less efficient than direct deletion or assignment-based approaches.

**Library Usage**

None of the test cases use any external libraries beyond JavaScript's built-in `Object.keys()`, `Object.entries()`, and `delete` statements.

Related benchmarks:

omit function testing (version: 5)

Comparing performance of: current vs new vs new delete vs new delete (assign) vs new delete (mutates)

Created: one year ago by: Registered User

Jump to the latest result

current

new

new delete

new delete (assign)

new delete (mutates)

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):