ES6 Everyday: Arrow Functions

Get ready for a fun one!

You know how to write a function in JavaScript:

function logSquareRoot(input)
{
  console.log(Math.sqrt(input));
}

logSquareRoot(16); // 4

Now let’s change this to an anonymous function that gets called on each member of an array:

[16, 36, 64].forEach(function(input) {
  
  console.log(Math.sqrt(input));
  
}); // 4, 6, 8

With ES6, we now have arrow functions that simplify this quite a bit:

[16, 36, 64].forEach((input) => {
  
  console.log(Math.sqrt(input));
  
}); // 4, 6, 8

And, since our function only has one argument, we can remove those parentheses too:

[16, 36, 64].forEach(input => {
  
  console.log(Math.sqrt(input));
  
}); // 4, 6, 8

Neat, eh?

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