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JavaScript JavaScript Array Iteration Methods Array Manipulation Practice map()

Posted by Ronald Greer
.a{fill-rule:evenodd;}techdegree seal-36
Ronald Greer
Front End Web Development Techdegree Graduate 56,430 Points

Unsure how to abbreviate these values.

Hey everyone, the challenge is asking me to use .map to abbreviate the values in the array but i have no idea what to implement so they abbreviate, any help is appreciated.

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

const abbreviatedDays = daysOfWeek.map(daysOfWeek => abbreviatedDays.split//what next?);

1 Answer

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

The example shows that the expected results are the first 3 characters of each name, so one tool that could be useful for this is the string method slice.

Ronald Greer
.a{fill-rule:evenodd;}techdegree seal-36
Ronald Greer
Front End Web Development Techdegree Graduate 56,430 Points

I tried the slice method out but now I'm getting the error that the abbreviatedDays identifier has already been used, how can i fix this and pass the challenge? current code: 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 let abbreviatedDays = daysOfWeek.map(daysOfWeek => abbreviatedDays.slice(0, 2));

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

The variable is already declared on line 2, so you just want to make an assignment to it (no "let" or "const").

Also, when creating the arrow function for "map" to use, remember the item on the left side of the arrow is simply a parameter name, which should also be used on the right side to indicate what will be done to each argument. To reduce chances for confusion, you might avoid re-using either of the variable names as the parameter name.