Benchmark: object method scope lookup

Script Preparation code:

var arrow = x => x + 1;

var object = {
  useHoistedGlobal(x) {
  	return hoistedGlobal(x);
  },
  useArrow(x) {
    return arrow(x);
  },
  useOwn(x) {
    return this._own(x);
  },
  _own(x) {
    return x + 1;
  }
}

function hoistedGlobal(x) {
  return x + 1;
}

var n = 420;

Tests:

hoisted global
n = object.useHoistedGlobal(1);
use arrow
n = object.useArrow(1);
use own
n = object.useOwn(1);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
hoisted global
use arrow
use own

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/17.5 Safari/605.1.15

Browser/OS: Safari 17 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
hoisted global	2484165.0 Ops/sec
use arrow	2535650.0 Ops/sec
use own	3562874.0 Ops/sec

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

LLMs can make mistakes. Check important info.

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

**Benchmark Definition JSON:**

The provided benchmark definition represents an object method scope lookup test case. It defines a JavaScript function `arrow` that takes an input `x` and returns `x + 1`. This function is then used within another object, which has three methods:

1. `useHoistedGlobal(x)`: This method calls the global variable `hoistedGlobal(x)` with the input `x`.
2. `useArrow(x)`: This method directly uses the defined arrow function `arrow(x)` to perform the calculation.
3. `useOwn(x)`: This method calls a local property `_own(x)` of the object, which returns `x + 1`.

The benchmark script prepares these methods and assigns them to the object, along with a global variable `n` initialized to `420`. The objective is to measure the performance difference between using the global variable, the arrow function, or the own method (`useOwn(x)`) to perform the calculation.

**Options Compared:**

The benchmark compares three different approaches:

1. **Hoisted Global**: Using the global variable `hoistedGlobal(x)` to perform the calculation.
2. **Arrow Function**: Directly using the defined arrow function `arrow(x)` to perform the calculation.
3. **Own Method (`useOwn(x)`)**: Calling a local property `_own(x)` of the object to perform the calculation.

**Pros and Cons:**

1. **Hoisted Global**:
	* Pros: Simple, well-established syntax, easy to read and maintain.
	* Cons: May lead to performance issues due to global variable lookups, potential for conflicts with other code.
2. **Arrow Function**:
	* Pros: Concise, expressive syntax, good performance characteristics.
	* Cons: Limited compatibility with older browsers or environments that don't support arrow functions.
3. **Own Method (`useOwn(x)`)**:
	* Pros: Encapsulation, encapsulation of the calculation logic within the object, potential for better performance due to reduced scope lookups.
	* Cons: Less intuitive syntax for some developers, may require additional code to implement.

**Library and Special JS Features:**

The benchmark uses a JavaScript function `hoistedGlobal(x)` which is not part of any standard library. This function is likely used to simulate a global variable lookup in a hypothetical scenario.

There are no special JavaScript features (e.g., async/await, destructuring) used in this benchmark.

**Other Alternatives:**

To write similar benchmarks, you could consider testing the following alternative approaches:

1. **Closure**: Using a closure to encapsulate the calculation logic within an object or function.
2. **Function Expression**: Using a function expression instead of a regular function declaration.
3. **Generator Functions**: Using generator functions for asynchronous calculations.

Keep in mind that the choice of approach depends on the specific requirements and constraints of your project.

Related benchmarks:

object method scope lookup (version: 0)

Comparing performance of: hoisted global vs use arrow vs use own

Created: 4 years ago by: Guest

Jump to the latest result

hoisted global

use arrow

use own

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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