FAQ: Advanced Object Types - Extending Interfaces

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This community-built FAQ covers the “Extending Interfaces” exercise from the lesson “Advanced Object Types”.

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This exercise can be found in the following Codecademy content:

Learn TypeScript

FAQs on the exercise Extending Interfaces

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Hello, I think that in this excercise is a problem with code structure. In index.ts, there is interface Developer defined at the top of the file and we need to add Human interface with name and hobbies (point 1 of excercise). Then in point 2, we need to add the members from Human to the Developer interface using the extends keyword.
As I understand, we need to write something like that:

interface Human extends Developer{
  name: string,
  hobbies: string[]
}

but this solution causes an error. When I click on the View Solution, the code example is inversed - we have Human interface at the top with Developer interface under it. It is really confusing why according to the excercise description we need to add our Human interface under the Developer interface, but solution is the other way round?

3

I don’t think the order really matters with Typescript. It might just be to pass the test made by the team. Try it out on https://www.typescriptlang.org/play and see if you get any errors