mirror of https://github.com/rust-lang/rust
41 lines
850 B
Rust
41 lines
850 B
Rust
#![feature(associated_type_defaults)]
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// Having a cycle in assoc. type defaults is okay...
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trait Tr {
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type A = Self::B;
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type B = Self::A;
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}
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impl Tr for () {}
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impl Tr for u8 {
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type A = u8;
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}
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impl Tr for u16 {
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type B = ();
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}
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impl Tr for u32 {
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type A = ();
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type B = u8;
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}
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// ...but not in an impl that redefines one of the types.
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impl Tr for bool {
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type A = Box<Self::B>;
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//~^ ERROR overflow evaluating the requirement `<bool as Tr>::A == _`
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}
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// (the error is shown twice for some reason)
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impl Tr for usize {
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type B = &'static Self::A;
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//~^ ERROR overflow evaluating the requirement `<usize as Tr>::B == _`
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}
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fn main() {
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// We don't check that the types project correctly because the cycle errors stop compilation
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// before `main` is type-checked.
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// `defaults-cyclic-pass-1.rs` does this.
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}
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