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Enforce required parameters

In JavaScript, you can enforce required parameters in functions by throwing an error if a parameter is missing. This can help catch bugs early and ensure that your functions are used correctly.

Here’s a simple JavaScript snippet to achieve this:

const throwIfMissing = () => {
  throw new Error('You have missing param!');
};
const func = (requiredParam = throwIfMissing()) => {
  // your code here
};

Explanation

  • throwIfMissing: This function throws an error when called.
  • requiredParam = throwIfMissing(): This sets the default value of requiredParam to the result of throwIfMissing(), which will throw an error if requiredParam is not provided.

Usage

To use this pattern, simply define your function with the required parameters and use the throwIfMissing function to enforce them:

func(); // Throws an error: "You have missing param!"
func('value'); // Works as expected

This ensures that the function is always called with the required parameters.