AI solution for JavaScript Coding Question on BFE.dev
61. create your own `Function.prototype.call`

Here is a possible implementation of myCall function:

function myCall(func, thisArg, ...args) {
  if (typeof func !== 'function') {
    throw new TypeError('First argument must be a function');
  }

  thisArg = thisArg || window; // default to window if not provided

  const key = Symbol('temp_key'); // create a unique symbol as the temporary property name
  thisArg[key] = func; // attach the function to the thisArg object using the temporary property
  const result = thisArg[key](...args); // invoke the function with the given arguments
  delete thisArg[key]; // remove the temporary property from the object
  return result; // return the result of the function invocation
}

Explanation:

1. The myCall function takes at least two arguments: func (the function to be called) and thisArg (the value of this inside the function).
2. It also takes zero or more additional arguments (...args) that will be passed to the function as its arguments.
3. If func is not a function, it throws a TypeError.
4. If thisArg is not provided or is null/undefined, it defaults to window.
5. It creates a unique symbol (key) as the temporary property name to avoid clash with existing properties.
6. It attaches the func to the thisArg object using the temporary property.
7. It invokes the func using the thisArg as this and the given arguments (...args).
8. It removes the temporary property from the thisArg object.
9. It returns the result of the function invocation.

Example usage:

function greet(name) {
  console.log(`Hello, ${name}! My name is ${this.name}.`);
}

const person = { name: 'Alice' };

myCall(greet, person, 'Bob');
// Output: "Hello, Bob! My name is Alice."

myCall(greet, null, 'Charlie');
// Output: "Hello, Charlie! My name is undefined." (defaulting to window)