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335d05aee5
- Point at type that should derive `PartialEq` to be structural.
- Point at manual `impl PartialEq`, explaining that it is not sufficient to be structural.
```
error: constant of non-structural type `MyType` in a pattern
--> $DIR/const-partial_eq-fallback-ice.rs:14:12
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LL | struct MyType;
| ------------- `MyType` must be annotated with `#[derive(PartialEq)]` to be usable in patterns
...
LL | const CONSTANT: &&MyType = &&MyType;
| ------------------------ constant defined here
...
LL | if let CONSTANT = &&MyType {
| ^^^^^^^^ constant of non-structural type
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note: the `PartialEq` trait must be derived, manual `impl`s are not sufficient; see https://doc.rust-lang.org/stable/std/marker/trait.StructuralPartialEq.html for details
--> $DIR/const-partial_eq-fallback-ice.rs:5:1
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LL | impl PartialEq<usize> for MyType {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
```
19 lines
328 B
Rust
19 lines
328 B
Rust
#![allow(warnings)]
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struct MyType;
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impl PartialEq<usize> for MyType {
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fn eq(&self, y: &usize) -> bool {
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true
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}
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}
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const CONSTANT: &&MyType = &&MyType;
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fn main() {
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if let CONSTANT = &&MyType {
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//~^ ERROR constant of non-structural type `MyType` in a pattern
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println!("did match!");
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}
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}
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