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JavaScript Practice forEach in JavaScript Practice forEach forEach Practice - 2

Hamzah Iqbal
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Hamzah Iqbal
Full Stack JavaScript Techdegree Student 11,145 Points
Posted by Hamzah Iqbal
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Hamzah Iqbal
Full Stack JavaScript Techdegree Student 11,145 Points

Why is it that the first Element is returned in forEach loop?

Doing the challenge, I realized that only the first element gets returned.

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





  days.forEach(day => dayAbbreviations = day.substring(0,2));
// dayAbbreviations should be: ['Su', 'Mo', 'Tu', 'We', 'Th', 'Fr', 'Sa']

Output: "Su"

Also why does it return undefined, if I store the value in this way:

dayAbbreviations =   days.forEach(day =>  day.substring(0,2));
app.js 
const days = ['Sunday', 'Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday'];
let dayAbbreviations = [];





  days.forEach(day => dayAbbreviations = day.substring(0,2));
// dayAbbreviations should be: ['Su', 'Mo', 'Tu', 'We', 'Th', 'Fr', 'Sa']
// Write your code below

1 Answer

Blake Larson
Blake Larson
13,014 Points
Blake Larson
Blake Larson
13,014 Points

For Each day you want to push the first two letters of the day into dayAbbreviations.

days.forEach(day => dayAbbreviations.push(day.substring(0,2)));

The forEach method actually has no return value so it will always return undefined. Try using .map() instead.