40 lines
800 B
Rust
40 lines
800 B
Rust
// Forbid assignment into a dynamically sized type.
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#![feature(unsized_tuple_coercion)]
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type Fat<T> = (isize, &'static str, T);
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#[derive(PartialEq,Eq)]
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struct Bar;
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#[derive(PartialEq,Eq)]
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struct Bar1 {
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f: isize
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}
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trait ToBar {
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fn to_bar(&self) -> Bar;
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fn to_val(&self) -> isize;
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}
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impl ToBar for Bar1 {
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fn to_bar(&self) -> Bar {
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Bar
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}
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fn to_val(&self) -> isize {
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self.f
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}
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}
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pub fn main() {
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// Assignment.
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let f5: &mut Fat<dyn ToBar> = &mut (5, "some str", Bar1 {f :42});
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let z: Box<dyn ToBar> = Box::new(Bar1 {f: 36});
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f5.2 = Bar1 {f: 36};
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//~^ ERROR mismatched types
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//~| expected `dyn ToBar`, found `Bar1`
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//~| expected trait object `dyn ToBar`
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//~| found struct `Bar1`
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//~| ERROR the size for values of type
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}
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