Benchmark: bind vs lambda - MeasureThat.net

Script Preparation code:

function dosmthg(msg) {
  console.log(this, msg);
}

const test1 = (msg) => {
  dosmthg(msg);
}

const test2 = dosmthg.bind(this);

Tests:

direct call
test1("World");
bind
test2("World");

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
direct call
bind

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 12 days ago)

User agent: Mozilla/5.0 (Linux; Android 10; K) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Mobile Safari/537.36

Browser/OS: Chrome Mobile 131 on Android

View result in a separate tab

Test name	Executions per second
direct call	46017.6 Ops/sec
bind	47519.0 Ops/sec

Autogenerated LLM Summary (model gpt-4o-mini, generated 26 days ago):

LLMs can make mistakes. Check important info.

The benchmark defined compares two approaches to function invocation in JavaScript: using a direct call to a function and using the `bind` method of the function. Here's a breakdown of the benchmark's components, the options being compared, their pros and cons, and other considerations.

### Benchmark Breakdown

1. **Function Definition**: 
   - The benchmark starts with a function `dosmthg(msg)` which logs its context (`this`) and a message. 
   - Two different ways of invoking `dosmthg` are established:
     - `test1`: Arrow function that directly calls `dosmthg`.
     - `test2`: Uses `bind` to create a new function that permanently sets the context (`this`) of `dosmthg`.

2. **Test Cases**:
   - **Test Case 1**: `"test1(\"World\");"` (direct call)
   - **Test Case 2**: `"test2(\"World\");"` (using `bind`)

### Options Compared

- **Direct Call (`test1`)**: This approach uses an arrow function that calls `dosmthg` directly. The context of `this` is inherited from the surrounding scope where the arrow function was defined.
  
- **Function Binding (`test2`)**: This method calls the `bind` function on `dosmthg`. The `bind` method creates a new function that, when called, has its `this` keyword set to the provided value (in this case, the value of `this` at the time of `bind`).

### Pros and Cons

- **Direct Call (`test1`)**:
  - **Pros**:
    - Typically faster than using `bind` since it directly invokes the function without creating an intermediary function.
    - The context of `this` can be correctly managed using the lexical scoping of arrow functions.
  - **Cons**:
    - Less flexible compared to `bind`, as the context cannot be changed dynamically after function creation.

- **Function Binding (`test2`)**:
  - **Pros**:
    - Provides a way to explicitly set the context of `this`, making it easier to ensure that the correct context is used, especially when functions are passed as callbacks or executed in different contexts.
    - Useful for maintaining method context when passing methods as arguments.
  - **Cons**:
    - Involves some overhead since it creates a new function, which might lead to slightly slower performance compared to direct calls.
    - The created function may consume more memory since each call to `bind` generates a new function.

### Other Considerations

- Performance in actual applications may vary based on the JavaScript engine and environment. In the given results, while `bind` executed slightly more times per second than the direct call, the performance difference is relatively small, indicating that the overhead introduced by `bind` may not significantly affect typical use cases where context binding is required.
  
- Consumers of this benchmark should consider the specific needs of their applications. If speed is a critical concern and the context of `this` does not frequently change, direct function calls may suffice. However, if there are instances where proper context management is essential, using `bind` is necessary.

### Alternatives

Other approaches to managing function contexts in JavaScript include:

- **Call and Apply Methods**: Both can invoke a function with a specified `this` context. They are suited for one-time calls rather than creating bound functions.
- **Using Classes**: When working with methods that need specific context, using ES6 classes allows for more structured approaches to maintaining context.
- **Function Composition**: Higher-order functions can encapsulate behavior and manage context implicitly.

Understanding these differences allows developers to select the most suitable method for invoking functions based on their specific context requirements and performance considerations.

Related benchmarks:

bind vs lambda (version: 1)

Comparing performance of: direct call vs bind

Created: 26 days ago by: Guest

Jump to the latest result

direct call

bind

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model gpt-4o-mini, generated 26 days ago):