Code
// inspired by https://github.com/rust-lang/rust/issues/130495
struct T(String);
impl PartialEq<String> for T {
fn eq(&self, other: &String) -> bool {
&self.0 == other
}
}
fn main() {
String::from("123") == T(String::from("123"));
}Current output
error[E0277]: can't compare `String` with `T`
--> src/main.rs:11:25
|
11 | String::from("123") == T(String::from("123"));
| ^^ no implementation for `String == T`
|
= help: the trait `PartialEq<T>` is not implemented for `String`
= help: the following other types implement trait `PartialEq<Rhs>`:
`String` implements `PartialEq<&str>`
`String` implements `PartialEq<Cow<'_, str>>`
`String` implements `PartialEq<str>`
`String` implements `PartialEq`
For more information about this error, try `rustc --explain E0277`.
error: could not compile `playground` (bin "playground") due to 1 previous errorDesired output
error[E0277]: can't compare `String` with `T`
--> src/main.rs:11:25
|
11 | String::from("123") == T(String::from("123"));
| ^^ no implementation for `String == T`
|
= help: the trait `PartialEq<T>` is not implemented for `String`
= help: the following other types implement trait `PartialEq<Rhs>`:
`String` implements `PartialEq<&str>`
`String` implements `PartialEq<Cow<'_, str>>`
`String` implements `PartialEq<str>`
`String` implements `PartialEq`
= note: `T` implements `PartialEq<String>`
help: consider swapping the equality
|
11 | T(String::from("123")) == String::from("123");
| ~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~
For more information about this error, try `rustc --explain E0277`.
error: could not compile `playground` (bin "playground") due to 1 previous errorRationale and extra context
In this case where T implements PartialEq<String>, swapping the equality is a good way to fix it.
Although #132404 has implemented this, it only covers the case where error[0308]: mismatched types occurs.
Other cases
No response
Rust Version
1.84.0-nightly (2024-10-15 e7c0d27) (playground)
Anything else?
No response
Code
Current output
Desired output
Rationale and extra context
In this case where
TimplementsPartialEq<String>, swapping the equality is a good way to fix it.Although #132404 has implemented this, it only covers the case where
error[0308]: mismatched typesoccurs.Other cases
No response
Rust Version
1.84.0-nightly (2024-10-15 e7c0d27) (playground)
Anything else?
No response