My favorite Rust function

Re:My favorite Rust function by millstone on Saturday October 12, 2019 @09:09PM (#21237546)

    let x = String::from("abc");
    std::mem::drop(&x);
    std::mem::drop(&x);
    std::mem::drop(&x);
    std::mem::drop(&x);

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Re:My favorite Rust function by hathawsh on Saturday October 12, 2019 @10:20PM (#21237855)

FWIW, that won't compile because std::mem::drop requires ownership of the object being passed; your code is trying to pass a reference instead.

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Re:My favorite Rust function by lpghatguy on Saturday October 12, 2019 @10:25PM (#21237878)

This code compiles just fine. It doesn't do anything since immutable references are Copy, and so dropping them doesn't do anything.

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Re:My favorite Rust function by hathawsh on Saturday October 12, 2019 @10:31PM (#21237912)

Oh right, I forgot about the interaction with generics in this case. Semantically, I suppose it's creating and dropping a reference 4 times.

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Re:My favorite Rust function by steveklabnik on Saturday October 12, 2019 @10:27PM (#21237893)

This should compile, &T is Copy and so it will not really do anything, but it will still compile.

On my phone so I can’t triple check, but there’s no bound on T, you can pass in any type.

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