Understanding Rust Error E0252
Introduction
Rust error E0252 occurs when two items with the same name are imported in the same scope without differentiating them. In this article, we will cover how to resolve this error by using aliases, using fully qualified paths, and going through code examples.
Basic Example
Let's illustrate Rust error E0252 with the following erroneous code example from the Rust documentation: use foo::baz; use bar::baz; // error, do `use bar::baz as quux` instead fn main() {} mod foo { pub struct baz; } mod bar { pub mod baz {} } In this example, we have a module `foo` with a public struct `baz` and a module `bar` with a public module `baz`. The error occurs when we attempt to import both `baz` items into the main scope.
Using Aliases
One way to resolve this error is by using aliases. By giving one or both items a different local name, we can avoid the naming conflict. In the example below, we use the `as` keyword to assign a new local name `foo_baz` for `foo::baz`: use foo::baz as foo_baz; use bar::baz; // ok! fn main() {} mod foo { pub struct baz; } mod bar { pub mod baz {} } Now, the main scope has a reference to `foo::baz` as `foo_baz` and to `bar::baz` as `baz`, eliminating the error.
Using Fully Qualified Paths
Another way to resolve Rust error E0252 is by using fully qualified paths. Instead of importing both items with the same name into the main scope, we can reference one or both of them using their full paths. Here is an example: use bar::baz; fn main() { let x = foo::baz; // ok! } mod foo { pub struct baz; } mod bar { pub mod baz {} } In this case, we only import `bar::baz` and reference `foo::baz` using the full path `foo::baz`.
Conclusion
To avoid Rust error E0252, we need to ensure that same-named items imported into the same scope have either unique aliases or are referenced using their fully qualified paths. Aliases can be defined using the `as` keyword, and fully qualified paths can be used directly for referencing items in the code.