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JavaScript Practice forEach in JavaScript Practice forEach forEach Practice - 2

Posted by Taylor Hall
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Taylor Hall
Front End Web Development Techdegree Graduate 14,496 Points

Why doesn't this work?

const days = ['Sunday', 'Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday']; let dayAbbreviations = [];

// dayAbbreviations should be: ['Su', 'Mo', 'Tu', 'We', 'Th', 'Fr', 'Sa'] // Write your code below

dayAbbreviations = days.forEach(day => day.slice(0, 1));

app.js 
const days = ['Sunday', 'Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday'];
let dayAbbreviations = [];

// dayAbbreviations should be: ['Su', 'Mo', 'Tu', 'We', 'Th', 'Fr', 'Sa']
// Write your code below

dayAbbreviations = days.forEach(day => day.slice(0, 1));

1 Answer

John Johnson
John Johnson
11,789 Points
John Johnson
John Johnson
11,789 Points

forEach attempts to perform an action on each iteration of the array, but it unfortunately cannot return an array itself. If you run this in the console, you'll see that it returns undefined

Your solution attempts to set dayAbbreviations equal to a JS function that will return undefined.

For the solution, you don't actually need to set dayAbbreviations equal to anything. You'll actually want the action preformed on each iteration of forEach to append the sliced string to the dayAbbreviations list.

An additional tip: when you slice(x, y) x = 0-based starting position y = 0-based position to end before (basically, this number is non-inclusive)

So you'll actually want slice(0, 2)