arrow_functions_with_this_keyword_intro.js

// Let's declare a variable of type array
let numbers = [1, 2, 3];

// Let's write a function with old style
function calculateNumbers() {
	this.total = 0;
	numbers.forEach(function(singleNumber) {
		// Here the "this" keyword is pointing to the wrong location.
		// The "this" keyword is pointing towards the current function instead of outer function.
    		this.total += singleNumber;
	});
	return total;
}

// Now see how we can solve this problem using the arrow function
const calculateNumbers = () => {
	this.total = 0;
	// Now the keyword "this" points to the outer function
	// Correct implementation
	numbers.forEach(singleNumber => (this.total += singleNumber));
	return total;
}