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:

     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:

     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.