() =>
indicates that a variable stores a function, eg:
//Long syntax
myFunction = () => {
//code..
};
//Shorthand (must be one-liner!) - returns the output without 'return' keyword
myFunction = () => /*code*/; //without parameter
myFunction = myParameter => /*code*/; //w parameter; concise body
myFunction = (myParameter) => { /*code*/ }; //w parameter; block body
Shorthand example:
getString = () => "tere"; //returns tere
getNumber = aNumber => aNumber * 2; //getNumber(15) returns 30
Foreach:
//Usual foreach loop
groceries.forEach(function(groceryItem) {
console.log(groceryItem);
});
//Shorthand
groceries.foreach(groceryItem => console.log(groceryItem));