alt Hacker NewsOOP and ownership are two concepts that mix poorly - ownership in the presence of OOP-like constructs is never simple.
The reason for that is OOP tends to favor constructs where each objects holds references to other objects, creating whole graphs, its not uncommon that from a single object, hundreds of others can be traversed.
Even something so simple as calling a member function from a member function becomes incredibly difficult to handle.
Tbh - this is with good reason, one of the biggest flaws of OOP is that if x.foo() calls x.bar() in the middle, x.bar() can clobber a lot of local state, and result in code that's very difficult to reason about, both for the compiler and the programmer.
And it's a simple case, OOP offers tons of tools to make the programmers job even more difficult - virtual methods, object chains with callbacks, etc. It's just not a clean programming style.
Edit: Just to make it clear, I am not pointing out these problems, to sell you or even imply that I have the solution. I'm not saying programming style X is better.
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It worked alright for Rust, and yes Rust does support OOP, there are many meanings to what is OOP from CS point of view.
I have ported Ray Tracing in One Weekend into Rust, while keeping the same OOP design from the tutorial, and affine types were not an impediment to interfaces, polymorphism and dynamic dispatch.
>one of the biggest flaws of OOP is that if x.foo() calls x.bar() in the middle, x.bar() can clobber a lot of local state, and result in code that's very difficult to reason about
That's more a problem of having mutable references, you'd have the same problem in a procedural language.
On the flipside, with OOP is usually quite easy to put a debugger breakpoint on a particular line and see the full picture of what the program is doing.
In diehard FP (e.g. Haskell) it's hard to even place a breakpoint, let alone see the complete state. In many cases, where implementing a piece of logic without carrying a lot of state is impossible, functional programming can also become very confusing. This is especially true when introducing certain theoretical concepts that facilitate working with IO and state, such as Monad Transformers.
I work at a D company. We tend to use OOP only for state owners with strict dependencies, so it's rare to even get cycles. It is extremely useful for modeling application state. However, all the domain data is described by immutable values and objects are accessed via parameters as much as fields.
When commandline apps were everywhere, people dreamed of graphical interfaces. Burdened by having to also do jobs that it was bad at, the commandline got a bad reputation. It took the dominance of the desktop for commandline apps to find their niche.
In a similar way, OOP is cursed by its popularity. It has to become part of a mixed diet so that people can put it where it has advantages, and it does have advantages.