JavaScript Closures Example

closures.js

// console.log(sum(2,3));   // Outputs 5 
// console.log(sum(2)(3));  // Outputs 5 


function sum(x){
    if (arguments.length == 2){
        // In functions arguments received as array. 
        // We need to check if their is two or one argument in array. 
       return arguments[0] + arguments[1];
    } else {
        return function (y) {
            return x + y;
        }
    }
}