Benchmark: In objects: shorthand vs arrow vs normal

HTML Preparation code:

<!--your preparation HTML code goes here-->

Script Preparation code:

let val = 0

const obj = {
  getVal() { return val; },
  setVal(x) { val = x; },
  
  getValArrow: () => { return val; },
  setValArrow: (x) => { val = x; },
      
  getValFn: function() { return val },
  setValFn: function(x) { val = x },
}

Tests:

Shorthand
obj.getVal() obj.setVal(1) obj.getVal()
Arrow
obj.getValArrow() obj.setValArrow(1) obj.getValArrow()
Normal
obj.getValFn() obj.setValFn(1) obj.getValFn()

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Shorthand
Arrow
Normal

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 15 days ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/118.0.0.0 Safari/537.36

Browser/OS: Chrome 118 on Windows

View result in a separate tab

Test name	Executions per second
Shorthand	40849080.0 Ops/sec
Arrow	42902076.0 Ops/sec
Normal	40397908.0 Ops/sec

Autogenerated LLM Summary (model gpt-4o-mini, generated 15 days ago):

LLMs can make mistakes. Check important info.

The benchmark titled "In objects: shorthand vs arrow vs normal" compares the performance of three different methods used to define functions within an object in JavaScript. The methods being evaluated are:

1. **Shorthand Method**: This utilizes the shorthand syntax for defining methods in an object.
   ```javascript
   getVal() { return val; },
   setVal(x) { val = x; },
   ```

2. **Arrow Function Method**: This employs arrow functions, which have a different scoping behavior compared to traditional functions.
   ```javascript
   getValArrow: () => { return val; },
   setValArrow: (x) => { val = x; },
   ```

3. **Normal Function Method**: This defines functions using the traditional `function` syntax.
   ```javascript
   getValFn: function() { return val; },
   setValFn: function(x) { val = x; },
   ```

### Performance Comparison

**Benchmark Results**
- **Arrow Functions**: Executions per second: **42,902,076**
- **Shorthand Methods**: Executions per second: **40,849,080**
- **Normal Functions**: Executions per second: **40,397,908**

### Pros and Cons of Each Approach

1. **Shorthand Method**:
   - **Pros**:
     - Concise syntax; easy to read and write.
     - Internally, shorthand methods are treated similarly to function declarations, offering optimal performance in many cases.
   - **Cons**:
     - Limited to object literals; cannot be used for functions outside of an object context.

2. **Arrow Functions**:
   - **Pros**:
     - Do not bind their own `this`, making them ideal for scenarios where you want to maintain the `this` context of the enclosing scope.
     - Concise syntax in function definition (especially for single-expression functions).
   - **Cons**:
     - Cannot be used as methods for objects if you need to access the object itself via `this`, which could hinder their usage in some scenarios.

3. **Normal Functions**:
   - **Pros**:
     - Familiar syntax; widely understood by JavaScript developers.
     - Can be used as methods and will correctly reference the calling object via `this`.
   - **Cons**:
     - More verbose compared to shorthand syntax and arrow functions.
     - Slightly less performant in some cases compared to shorthand methods and arrow functions when defined in an object context.

### Other Considerations

- All three methods are suitable for different use cases. Shorthand is often preferred for its readability and brevity, while arrow functions are chosen for their lexical scoping of `this`. Traditional functions are still important when the function's behavior relies on the `this` binding.
- The differences in performance noted in the benchmark are significant but may not affect most applications unless executed in performance-critical contexts (e.g., loops or high-frequency calls).
- This benchmark was conducted in Chrome 118 on a Windows desktop environment. Performance characteristics may vary across different browsers and operating systems, so it's advisable for developers to conduct their benchmarks in their deployment environments.

### Alternatives

Other alternatives for defining functions in JavaScript include:
- **Function Expressions**: Using function expressions and class-based methods in ES6 classes can also define methods similarly.
- **Prototypal Inheritance**: For larger applications where memory and performance are critical, you might consider using prototypal inheritance to define shared methods on prototypes rather than directly on objects.

In conclusion, this benchmark provides valuable insights into performance differences among method definitions in JavaScript objects, highlighting how modern JavaScript features can impact both code readability and execution efficiency.

Related benchmarks:

In objects: shorthand vs arrow vs normal (version: 1)

Comparing performance of: Shorthand vs Arrow vs Normal

Created: 15 days ago by: Guest

Jump to the latest result

Shorthand

Arrow

Normal

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model gpt-4o-mini, generated 15 days ago):