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JavaScript JavaScript Array Iteration Methods Array Manipulation Practice map()

Posted by Dwayne Bynum
Dwayne Bynum
10,408 Points

daysOfWeek.map((day)=>{day.substr(0,4)}); Using the curly Braces do not work in any of the challenges WHY?

Although using the arrow function without the curly braces is sometimes more concise the challenges do not accept it as correct syntax.

app.js 
const daysOfWeek = ["Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"];
let abbreviatedDays;

// abbreviatedDays should be: ["Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"]
// Write your code below

abbreviatedDays = daysOfWeek.map((day)=>{day.slice(0,4)});

1 Answer

Steven Parker
Steven Parker
231,272 Points
Steven Parker
Steven Parker
231,272 Points

First, if you want 3 characters, the 2nd parameter of "slice" should be "3" instead of "4".

Then, either form of the function will work, but you must observe the other differences:

abbreviatedDays = daysOfWeek.map(day => day.slice(0,3));         //compact form has no braces
abbreviatedDays = daysOfWeek.map(day => {return day.slice(0,3);}); //long form needs "return"
Dwayne Bynum
Dwayne Bynum
10,408 Points

Thanks for the Help!