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…nikomatsakis Stabilize `let` bindings and destructuring in constants and const fn r? @Centril This PR stabilizes the following features in constants and `const` functions: * irrefutable destructuring patterns (e.g. `const fn foo((x, y): (u8, u8)) { ... }`) * `let` bindings (e.g. `let x = 1;`) * mutable `let` bindings (e.g. `let mut x = 1;`) * assignment (e.g. `x = y`) and assignment operator (e.g. `x += y`) expressions, even where the assignment target is a projection (e.g. a struct field or index operation like `x[3] = 42`) * expression statements (e.g. `3;`) This PR does explicitly *not* stabilize: * mutable references (i.e. `&mut T`) * dereferencing mutable references * refutable patterns (e.g. `Some(x)`) * operations on `UnsafeCell` types (as that would need raw pointers and mutable references and such, not because it is explicitly forbidden. We can't explicitly forbid it as such values are OK as long as they aren't mutated.) * We are not stabilizing `let` bindings in constants that use `&&` and `||` short circuiting operations. These are treated as `&` and `|` inside `const` and `static` items right now. If we stopped treating them as `&` and `|` after stabilizing `let` bindings, we'd break code like `let mut x = false; false && { x = true; false };`. So to use `let` bindings in constants you need to change `&&` and `||` to `&` and `|` respectively.
…li-obk Const-stabilize `const_int_ops` + `const_ip` r? @oli-obk I've added T-lang since this affects intrinsics and the operational semantics of Rust's `const fn` fragment. This PR depends on rust-lang#57105 but the FCP intent does not. ## Stable APIs proposed for constification + `const_int_ops`: + `count_ones` + `count_zeros` + `leading_zeros` + `trailing_zeros` + `swap_bytes` + `from_be` + `from_le` + `to_be` + `to_le` + `const_ip` + `Ipv4Addr::new` ## Unstable APIs constified + `const_int_conversion`: + `reverse_bits`
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@bors r+ p=2 |
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📌 Commit 713551c has been approved by |
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⌛ Testing commit 713551c with merge d6753e808df6f78f5e46c67f4490c1d0827be96d... |
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💔 Test failed - checks-travis |
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The job Click to expand the log.I'm a bot! I can only do what humans tell me to, so if this was not helpful or you have suggestions for improvements, please ping or otherwise contact |
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Successful merges:
letbindings and destructuring in constants and const fn #57175 (Stabilizeletbindings and destructuring in constants and const fn)const_int_ops+const_ip#57234 (Const-stabilizeconst_int_ops+const_ip)Failed merges:
r? @ghost