mirror of https://github.com/rust-lang/rust
31 lines
685 B
Rust
31 lines
685 B
Rust
enum DoubleOption<T> {
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FirstSome(T),
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AlternativeSome(T),
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Nothing,
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}
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fn this_function_expects_a_double_option<T>(d: DoubleOption<T>) {}
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fn main() {
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let n: usize = 42;
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this_function_expects_a_double_option(n);
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//~^ ERROR mismatched types
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//~| HELP try wrapping the expression in a variant of `DoubleOption`
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}
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// But don't issue the "try using a variant" help if the one-"variant" ADT is
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// actually a one-field struct.
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struct Payload;
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struct Wrapper { payload: Payload }
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struct Context { wrapper: Wrapper }
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fn overton() {
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let _c = Context { wrapper: Payload{} };
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//~^ ERROR mismatched types
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//~| try wrapping the expression in `Wrapper`
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}
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