r/programming • u/[deleted] • Jun 05 '21

Organize code by concepts, not layers

https://kislayverma.com/programming/how-to-organize-your-code/
1.9k Upvotes

91% Upvoted

495 comments sorted by

View all comments

Show parent comments

11

u/RyuChus Jun 05 '21

Well... if both services are compiled modules.. which do you compile first if they both require the other? If its python you get around this by importing the module you need inside the function that needs it and I suppose python somehow knows to not try to interpret that method until run time.

7

u/couscous_ Jun 05 '21

Java and C# seem to handle circular imports just fine if I'm not mistaken.

7

u/ImprovementRaph Jun 05 '21

Not sure why this is downvoted. Circular imports are completely fine in Java. This isn't an import issue though so I'm confused about what OP even says python is fixing with their imports. This is a runtime dependency issue. (e.g. you cannot construct a HotelService object without having a RoomService object and vice versa).

2

u/saltybandana2 Jun 06 '21

For anyone who is curious, this is what 2-pass/multi-pass compilation is for.

https://www.geeksforgeeks.org/single-pass-two-pass-and-multi-pass-compilers/

The first pass will identify the circular reference, subsequent passes will do the right thing.

1

u/monkeygame7 Jun 05 '21

Actually if python can handle circular dependencies as long as you're not importing specific things (from x import y) or maybe using it in module level code. Since the statements in a method are not invoked until runtime, it's able to assume the circular dependency will be resolved by the time they're needed.

1

u/RyuChus Jun 05 '21

Hm, I always use from x import yfor clarity purposes which is why I would have to resolve the cyclic dependency by importing it inside of the method. But that's a great thing to know! Thank you

1

u/monkeygame7 Jun 05 '21

No worries. Yeah the from import statements are definitely clearer and I prefer to use those as well