[Setup] Structure of Files and Nested Types

[kkarenvoo05]

Description

For feedback on my Assignment #1, I was told to void nested types for now.

Reproduction

For example, for the Patient class, I nested the age variable within this class. Is it recommended that I create an entire separate file for this variable or can I declare this variable within the same file as the Patient class, but not nested within this class? Thank you!

Expected behavior

I am assuming the behavior would be the same, but it is more of a question of style.

Additional context

No response

Code of Conduct

• I agree to follow this course's Code of Conduct and Contributing Guidelines

[PSchmiedmayer]

Hi @kkarenvoo05,

Thank you for asking a question here on GitHub!

I think there might be a confusion between nested types (see Apple Swift Documentation) and type properties (great article provide an overview of what's possible in Swift).

Nested types are a great way to structure types that are very closely bound to each other and where a type-based name scoping makes sense (such as the cards example in the documentation). The feedback for assignment 1 was probably targeted to a nested type that would make sense to be used across the app and whose scope goes beyond a single type. Therefore it would make sense to put it in a separate file & outside of the scope of a parent type.

Properties belonging to a type always have to be defined within the scope of a type & should ideally be defined where the type itself is defined (same file). Sometimes we use separate files for longer extensions and protocol implementations where computed properties or other elements are moved to different files. So computed properties such as var age: Int { /*...*/ } which is most likely a computed property accessing the let dateOfBirth: Date property should normally be defined within the same scope and file of the surrounding type (most likely struct Patient in your case).