76 lines
1.5 KiB
Rust
76 lines
1.5 KiB
Rust
mod mul1 {
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pub trait Mul {}
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}
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mod mul2 {
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pub trait Mul {}
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}
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mod mul3 {
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enum Mul {
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Yes,
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No
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}
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}
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mod mul4 {
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type Mul = String;
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}
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mod mul5 {
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struct Mul{
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left_term: u32,
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right_term: u32
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}
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}
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#[derive(Debug)]
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struct Foo;
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// When we comment the next line:
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//use mul1::Mul;
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// BEFORE, we got the following error for the `impl` below:
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// error: use of undeclared trait name `Mul` [E0405]
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// AFTER, we get this message:
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// error: trait `Mul` is not in scope.
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// help: ...
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// help: you can import several candidates into scope (`use ...;`):
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// help: `mul1::Mul`
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// help: `mul2::Mul`
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// help: `std::ops::Mul`
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impl Mul for Foo {
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//~^ ERROR cannot find trait `Mul`
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}
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// BEFORE, we got:
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// error: use of undeclared type name `Mul` [E0412]
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// AFTER, we get:
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// error: type name `Mul` is not in scope. Maybe you meant:
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// help: ...
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// help: you can import several candidates into scope (`use ...;`):
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// help: `mul1::Mul`
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// help: `mul2::Mul`
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// help: `mul3::Mul`
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// help: `mul4::Mul`
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// help: and 2 other candidates
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fn getMul() -> Mul {
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//~^ ERROR cannot find type `Mul`
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}
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// Let's also test what happens if the trait doesn't exist:
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impl ThisTraitReallyDoesntExistInAnyModuleReally for Foo {
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//~^ ERROR cannot find trait `ThisTraitReallyDoesntExistInAnyModuleReally`
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}
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// Let's also test what happens if there's just one alternative:
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impl Div for Foo {
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//~^ ERROR cannot find trait `Div`
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}
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fn main() {
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let foo = Foo();
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println!("Hello, {:?}!", foo);
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}
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