es6-arrow-fn-intro.js

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// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/Arrow_functions
// ----------------------------------------------------------------------------

//-----------------------------# DIRECTIONS #----------------------------------

//    Before you start give the MDN docs on Arrow functions a read/skim.
//    Feel free to skip over anything related to "binding" or "this".

//    After doing this you should have a genearal idea of how to work
//    with arrow functions. You will see varirying examples of how arrow
//    functions can be used which will be a useful reference as you work
//    through the problems you are tasked with implementing below.

// ----------------------------------------------------------------------------
// ----------------------------------------------------------------------------

const rp = require('request-promise');
const awesomeArray = [ 1, 23, 5, 19, 15, 13, 5, 1, 18, 18, 1, 25];
const uri = 'https://www.metaweather.com/api/location/2490383/'
const options = { uri, json: true }


// Refactor this function to use an es6 arrow function:

function printPrettyDate(timestamp) {
  let date = new Date(timestamp);
  let prettyDate = date.toString().split(' ').slice(0,4).join(' ');

  console.log(prettyDate);
}


// ----------------------------------------------------------------------------
// Refactor the callback function to use an es6 arrow function.
// If a function only has one paramater, you don't need the enclosing parens.
// Make sure to omit the parens when refactoring the callback function.

let filteredAwesomeArray = awesomeArray.filter(function(item) {
  return item % 2;
})


// ----------------------------------------------------------------------------
// es6 Arrow functions can be written as an expression
// - In a single line with an *implicit* return.

// Refactor this function into a single line expression
// - No code block/curley braces
// - No return keyword

// Arrow functions w/ multiple params require parens

let sum = awesomeArray.reduce(function(a, b) {
  return a + b;
});


// ----------------------------------------------------------------------------
// Refactor the `fetchData` function declaration to use an arrow function.
// the function should only be a single line, using an *implicit* return.

function fetchData() {
  return {
    data: 'data'
  }
}


// ----------------------------------------------------------------------------
// Promise handlers are no different.
// Refactor the promise handler to use an arrow function

rp(options)
  .then(function(data) {
    console.log('Sun Rise:');
    printPrettyDate(data.sun_rise);
  })