1ad218f3af
As our implementation of MCP411 nears completion and we begin to solicit testing, it's no longer reasonable to expect testers to type or remember `BikeshedIntrinsicFrom`. The name degrades the ease-of-reading of documentation, and the overall experience of using compiler safe transmute. Tentatively, we'll instead adopt `TransmuteFrom`. This name seems to be the one most likely to be stabilized, after discussion on Zulip [1]. We may want to revisit the ordering of `Src` and `Dst` before stabilization, at which point we'd likely consider `TransmuteInto` or `Transmute`. [1] https://rust-lang.zulipchat.com/#narrow/stream/216762-project-safe-transmute/topic/What.20should.20.60BikeshedIntrinsicFrom.60.20be.20named.3F
33 lines
773 B
Rust
33 lines
773 B
Rust
//@ revisions: current next
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//@ ignore-compare-mode-next-solver (explicit revisions)
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//@[next] compile-flags: -Znext-solver
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//! The unit type, `()`, should be one byte.
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#![crate_type = "lib"]
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#![feature(transmutability)]
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#![allow(dead_code)]
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mod assert {
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use std::mem::{Assume, TransmuteFrom};
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pub fn is_transmutable<Src, Dst>()
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where
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Dst: TransmuteFrom<Src, {
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Assume::ALIGNMENT
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.and(Assume::LIFETIMES)
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.and(Assume::SAFETY)
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.and(Assume::VALIDITY)
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}>
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{}
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}
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#[repr(C)]
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struct Zst;
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fn should_have_correct_size() {
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assert::is_transmutable::<(), Zst>();
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assert::is_transmutable::<Zst, ()>();
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assert::is_transmutable::<(), u8>(); //~ ERROR cannot be safely transmuted
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}
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