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23,007 Pointshow does the => operator work in this forEach() method
how does the => operator work in this case never seen it used like this before
const fruits = ['apple', 'pear', 'cherry'];
fruits.forEach(fruit => console.log(fruit));
2 Answers
Jean-Luc Robitaille
13,864 PointsIt's a shorthand to write an arrow function.
let functionName = (parameters) => {
console.log("something");
}
In the shorthand syntax, if you have only 1 parameter, you can omit the parentheses. And if you only have 1 line of code, or only 1 action in your function body, you can write it without using brackets. So it becomes:
let functionName = parameters => console.log("something");
Check out the course teamtreehouse.com/library/getting-started-with-es2015-2 They talk about arrow function.
Juan Hurtado
2,243 PointsNormal way of doing a forEach
const fruits = ['apple', 'pear', 'cherry'];
fruits.forEach(function(fruit) {
console.log(fruit)
});
Using the => operator you are removing a few things from the way of writing the callback:
- function keyword
- parenthesis around the argument name
- curly braces surrounding the body of the callback e.g. console.log(fruit)
- replacing the callback console.log in the same line
Adding:
- => operator to denote what the callback returns
The purpose is to do the same but more concise.
Bear in mind both ways do the exact same thing