My favorite Rust function

Re:My favorite Rust function by edflsafoiewq on Saturday October 12, 2019 @08:20PM (#21237319)

The equivalent to drop in C++ would be

    template <class T>
    void drop(T&) = delete; // force callers to move

    template <class T>
    void drop(T&& x) {
        T drop_me(std::move(x));
    }

edit: fixed.

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Re:My favorite Rust function by Rusky on Saturday October 12, 2019 @08:53PM (#21237481)

This is not correct; moves must leave the value in a valid state, because its destructor will still run. The correct version is actually the same as Rust's:

    template <class T>
    void drop(T) {}

(Moving into a local in `drop(T&&)` also works.)

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Re:My favorite Rust function by edflsafoiewq on Saturday October 12, 2019 @09:02PM (#21237515)

You're correct, sorry (I did have that at one point...). But the equivalent of Rust's pass-by-moving is to pass an r-value reference. Passing a const reference to drop is certainly an error and should be disallowed.

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