Benchmark: import dataurl vs function constructor

HTML Preparation code:

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

Script Preparation code:

let url =
    `data:text/javascript,${encodeURIComponent(`
export function c() {
return 2+2+2
}
`)}`
async function a() {
    let c = await import(url)
    c()
    deferred.resolve()
}
async function b() {
    let d = Function('return 2+2+2')
    deferred.resolve()
}

Tests:

import
a()
Function constructor
b()

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
import
Function constructor

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (X11; CrOS x86_64 14541.0.0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/132.0.0.0 Safari/537.36

Browser/OS: Chrome 132 on Chrome OS 14541.0.0

View result in a separate tab

Test name	Executions per second
import	105083.3 Ops/sec
Function constructor	55454.5 Ops/sec

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

LLMs can make mistakes. Check important info.

In the provided benchmark, two different methods are compared for dynamically defining and executing JavaScript functions: using the `import()` syntax for loading a module and the `Function` constructor for creating a function inline.

### Comparison of Approaches

1. **Using `import()` (Asynchronous Module Loading)**:
   - **Test Name**: `import`
   - **Benchmark Definition**: `a()`
   - **Description**: This approach uses the `import()` function, which allows for asynchronous loading of JavaScript modules. In this benchmark, a string representation of a module is encoded as a data URL, which contains a function that performs a simple calculation (2 + 2 + 2).
   - **Pros**:
     - **Modularity**: Supports modular programming, allowing code to be organized into separate files which can improve maintainability.
     - **Scope Management**: Runs in a separate scope, reducing the risk of variable collisions.
     - **Async Loading**: Enables lazy-loading of modules, which can enhance loading times if modules aren't needed right away.
   - **Cons**:
     - **Performance Overhead**: There might be a performance overhead due to the async nature of `import()`, particularly in scenarios where the module is loaded frequently.
     - **Browser Support**: While most modern browsers support dynamic imports, there could be inconsistencies across older browsers.

2. **Using the `Function` Constructor**:
   - **Test Name**: `Function constructor`
   - **Benchmark Definition**: `b()`
   - **Description**: This method uses the `Function` constructor to evaluate a string as JavaScript code and return a new function. The code again performs the same calculation (2 + 2 + 2).
   - **Pros**:
     - **Simplicity**: It's a quick way to create functions without loading external resources.
     - **Performance**: It can be faster since there’s no need to fetch a module, particularly for simple functions.
   - **Cons**:
     - **Security**: This method can be more vulnerable to security issues, such as code injection, since it evaluates a string as code.
     - **Scope Limitations**: Variables defined outside the constructor are not accessible inside the created function (unless explicitly passed), making scope management less flexible.

### Benchmark Results

From the benchmark results:

- **`import` method** executed at **105,083.33 executions per second**.
- **`Function constructor`** executed at **55,454.55 executions per second**.

### Other Considerations

- **Use Cases**: The choice between these methods should be influenced by the context. For small utility functions that are performed repeatedly and need quick access, the `Function` constructor might be preferred. However, for larger applications that require modular code and better organization, the dynamic `import()` is usually more suitable.
  
- **Alternative Approaches**: 
  - **Script Tag Injection**: Dynamically adding a `<script>` tag to the DOM can also be an alternative for loading and executing scripts, though it has its own set of challenges, such as managing load times and dependencies.
  - **Webpack or Rollup**: Using build tools that bundle JavaScript modules is another alternative. They optimize and manage dependencies before code is executed.
  
In summary, while both methods achieve similar results in functionality, they differ in performance, security, and modularity. Careful consideration of use case requirements should guide the decision on which approach to use.

Related benchmarks:

import dataurl vs function constructor (version: 1)

Comparing performance of: import vs Function constructor

Created: one year ago by: Guest

Jump to the latest result

import

Function constructor

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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