Benchmark: Reflect.get vs direct access

HTML Preparation code:

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

Script Preparation code:

/*your preparation JavaScript code goes here
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async function globalMeasureThatScriptPrepareFunction() {
    // This function is optional, feel free to remove it.
    // await someThing();
}

Tests:

Reflect.get
const val = {} for (let i = 0; i < 1000; ++i) { val[i] = i val[i] = Reflect.get(val, i - 1) }
Direct access
const val = {} for (let i = 0; i < 1000; ++i) { val[i] = i val[i] = val[i - 1] }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Reflect.get
Direct access

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 4 months ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/143.0.0.0 Safari/537.36 Edg/143.0.0.0

Browser/OS: Chrome 143 on Windows

View result in a separate tab

Test name	Executions per second
Reflect.get	29446.6 Ops/sec
Direct access	100353.1 Ops/sec

Autogenerated LLM Summary (model gpt-4o-mini, generated one year ago):

LLMs can make mistakes. Check important info.

### Benchmark Overview

The provided benchmark compares two methods of accessing object properties in JavaScript: direct access versus using the `Reflect.get` method. It evaluates how each method performs in terms of execution speed by executing a simple loop that populates an object and retrieves values.

### Options Compared

1. **Reflect.get**: 
   - **Test Definition**:
     ```javascript
     const val = {};
     for (let i = 0; i < 1000; ++i) {
         val[i] = i;
         val[i] = Reflect.get(val, i - 1);
     }
     ```
   - **Description**: 
     This test uses the `Reflect.get` method to retrieve a property from the object `val`. The `Reflect` object is a built-in object in JavaScript that provides methods for interceptable JavaScript operations. `Reflect.get` specifically allows for property access on an object in a more controlled way.
   
2. **Direct Access**: 
   - **Test Definition**:
     ```javascript
     const val = {};
     for (let i = 0; i < 1000; ++i) {
         val[i] = i;
         val[i] = val[i - 1];
     }
     ```
   - **Description**:
     This test retrieves a property directly using standard object property access. It assigns `val[i - 1]` directly to `val[i]`.

### Performance Results

The benchmark results show:
- **Direct access**: 97,982 executions per second.
- **Reflect.get**: 32,096 executions per second.

### Pros and Cons

#### Reflect.get
- **Pros**: 
  - More explicit and can work with dynamic property names or when property names are not known ahead of time.
  - Useful in certain meta-programming scenarios where reflection is necessary.
  
- **Cons**:
  - Slower in terms of performance compared to direct access as shown in the benchmark, which can be a significant downside in performance-critical applications.
  - Slightly more complex syntax than simple property access.

#### Direct Access
- **Pros**:
  - Faster execution as it relies on the JavaScript engine's optimization for direct property access.
  - Simpler to read and understand, making it more straightforward for developers coming from various programming backgrounds.

- **Cons**:
  - Cannot be used for dynamic property access in the same way as `Reflect.get`.
  - Less flexible for use cases that involve manipulating the object structure dynamically.

### Other Considerations

While this benchmark focuses on two approaches to property access, there are alternative methods in JavaScript for accessing object properties, such as:

- **Bracket Notation**: Using square brackets to access properties (e.g., `val[i - 1]`). This is similar to direct access but allows for more dynamic property access and would perform similarly in speed.
- **Proxy Objects**: If more complex behavior or validation on property access is required; however, this would introduce significant complexity and potential performance overhead.

### Conclusion

In cases where performance is paramount, especially in tight loops or high-frequency operations, direct property access is the preferable option. `Reflect.get` is valuable for dynamic access needs or when engaging in meta-programming, but one should consider the performance trade-offs highlighted in this benchmark.

Related benchmarks:

Reflect.get vs direct access (version: 1)

Comparing performance of: Reflect.get vs Direct access

Created: one year ago by: Guest

Jump to the latest result

Reflect.get

Direct access

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model gpt-4o-mini, generated one year ago):