question: How to show the elements of an array with arrow functions?
I understand that given an array with elements, I pass the array as a parameter, but what I do not understand, is that it must go in the body of the function?
Can this be done with this type of function? Greetings
The arrow functions are simply shortcuts to assignable functions or callbacks to maintain the context in which they are called without making explicit% .bind . For example:
class A {
constructor () {
this.name = 'Letra A';
}
foo () {
setTimeout(function () {
console.log(this.name);
}, 3000);
}
}
new A().foo();
The previous example shows one of the problems thanks to which this new notation for functions was proposed. The above code prints undefined because this refers to window and not% A .
The above is solved in ES5 as follows:
setTimeout(function () {
console.log(this.name);
}.bind(this), 3000);
As of ES6, with the arrival of the arrow functions, the solution is simpler:
setTimeout(() => console.log(this.name), 3000);
Answering your question, the way to iterate over an arrangement is the same using ES6:
let names = ['John', 'Martha', 'Leslie'];
names.forEach(name => console.log(name));
['a', 2, 'c', 4].forEach(v => console.log(v));If you would like to evaluate it in ES5 it would be equivalent to:
['a', 2, 'c', 4].forEach(function(v) {
return console.log(v);
});