mirror of https://github.com/rust-lang/rust
36 lines
692 B
Rust
36 lines
692 B
Rust
// Test equality constraints in a where clause where the type being
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// equated appears in a supertrait.
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pub trait Vehicle {
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type Color;
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fn go(&self) { }
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}
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pub trait Car : Vehicle {
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fn honk(&self) { }
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}
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struct Black;
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struct ModelT;
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impl Vehicle for ModelT { type Color = Black; }
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impl Car for ModelT { }
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struct Blue;
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struct ModelU;
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impl Vehicle for ModelU { type Color = Blue; }
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impl Car for ModelU { }
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fn black_car<C:Car<Color=Black>>(c: C) {
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}
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fn blue_car<C:Car<Color=Blue>>(c: C) {
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}
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fn a() { black_car(ModelT); }
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fn b() { blue_car(ModelT); } //~ ERROR type mismatch
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fn c() { black_car(ModelU); } //~ ERROR type mismatch
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fn d() { blue_car(ModelU); }
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pub fn main() { }
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