Rust RAII is better than the Haskell bracket pattern(snoyman.com)

    struct Foo {
      Foo() { std::cout << "Foo()" << std::endl; }
      ~Foo() { std::cout << "~Foo()" << std::endl; }
    };

    {
        std::aligned_storage<sizeof(Foo),alignof(Foo)> foo;
        new(&foo) Foo;
        /* destructor never called even though a Foo
           lives in block scope and its storage is
           free'd
        */
    }

    union Foo {
      Foo() { std::cout << "Foo()" << std::endl; }
      ~Foo() { std::cout << "~Foo()" << std::endl; }
    };

    {
      Foo foo();
      /* destructor never called */
    }

    struct Foo;
    impl Drop for Foo {
        fn drop(&mut self) {
            println!("drop!");
        }
    }

    {
      let _ = std::mem::ManuallyDrop::<Foo>::new(Foo);
      /* destructor never called */
    }