I have the following sketch of an implementation: trait Listener { fn some_action(&mut self); fn commit(self); } struct FooListener {} impl Listener for FooListener { fn some_action(&m...

I know that std::unique_ptr is used when an object has only one owner and std::shared_ptr is used when an object has multiple owners. What does it mean to be the unique owner of an object? Does be...

fn func(s: *mut String, a: *mut i32) -> usize { println!("{}", unsafe { *s }); println!("{}", unsafe { *a }); unsafe { (*s).len() } } fn main() { let mut s = String::from("hello"); let mu...

I want to write a generic function that accepts any kind of string (&str/String) for convenience of the caller. The function internally needs a String, so I'd also like to avoid needless re-a...

I have some non-copyable type and a function that consumes and (maybe) produces it: type Foo = Vec<u8>; fn quux(_: Foo) -> Option<Foo> { Some(Vec::new()) } Now consider a type t...

Say there is an object A which owns an object B via std::unique_ptr<B>. Further B holds a raw pointer(weak) reference to A. Then the destructor of A will invoke the destructor of B, since it ...

I'm currently trying to write a little command line app in Rust and I've hit a wall with lifetimes. extern crate clap; use self::clap::{App, Arg}; use std::env; impl<'p> Params<'p> { ...

There is a great example of Rust's move semantics documented here: Rust Move Semantics on the Rust By Example website. I have a basic understanding of both cases demonstrated. The first being how ...

There is a vector resource that is allocated in line 2 of the program below. When the program ends, the vector resource is not owned. If a resource is not owned at all, when does it get reclaimed? ...

Perhaps I was trying to be too generic. (Original question below) Concretely, I have some dependency Dep of a class Foo. I also have a class MockDep and am defining a class TestFoo. Here is its con...

I'm primarily a C++ programmer, and I've grown used to having class templates like std::unique_ptr, std::shared_ptr, etc for expressing ownership of my objects. Does Delphi have anything that is si...

Handles have proper semantics other than pointers. So for me an example like this (extracted from the Rule of Zero): class module { public: explicit module(std::wstring const& name) : handle ...

I've written a static factory method that returns a new Foobar object populated from another data object. I've recently been obsessed with ownership semantics and am wondering if I'm conveying the ...

I'd like the destructor of my class to delete the entire object except for one of the members, which is deleted elsewhere. First of all, is this totally unreasonable? Assuming it's not, how do I do...

C++ is all about memory ownership - aka ownership semantics. It is the responsibility of the owner of a chunk of dynamically allocated memory to release that memory. So the question really be...