Beginner's TypeScript Tutorial (18 exercises)
Problem

Assigning Types to Variables

Here we have an interface that represents a user within our system:

interface User {
  id: number;
  firstName: string;
  lastName: string;
  isAdmin: boolean;
}

There's a function called getUserId that takes in a user, and returns its id.

Our test is currently failing, because it calls getUserId and passes in a defaultUser that doesn't match the User contract.

Challenge

Reference the TypeScript docs and determine how to change defaultUser so that our test will pass.

Code

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beginners-typescript-tutorial

/src/05-assigning-types-to-variables.problem.ts

Transcript

We've got a tricky problem here. We're using an interface user as a way to represent the user within our system. We've got a function down here called getUserId, which takes in a user and returns its ID.

Now, this getUserId (defaultUser) is failing. It's failing because this defaultUser is not meeting this user contract. If I were to change it...I would say id, 1, firstName, Matt, lastName, Pocock, isAdmin, true, then it's going to pass.

I don't want the error to be down here. I ideally want the error to be at this line or around here, because I want to make sure that my defaultUser is matching that user contract. Your job is to go through the TypeScript docs and work out how you would do this.