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+An item usage is ambiguous.
+
+Erroneous code example:
+
+```compile_fail,edition2018,E0659
+pub mod moon {
+    pub fn foo() {}
+}
+
+pub mod earth {
+    pub fn foo() {}
+}
+
+mod collider {
+    pub use crate::moon::*;
+    pub use crate::earth::*;
+}
+
+fn main() {
+    crate::collider::foo(); // ERROR: `foo` is ambiguous
+}
+```
+
+This error generally appears when two items with the same name are imported into
+a module. Here, the `foo` functions are imported and reexported from the
+`collider` module and therefore, when we're using `collider::foo()`, both
+functions collide.
+
+To solve this error, the best solution is generally to keep the path before the
+item when using it. Example:
+
+```edition2018
+pub mod moon {
+    pub fn foo() {}
+}
+
+pub mod earth {
+    pub fn foo() {}
+}
+
+mod collider {
+    pub use crate::moon;
+    pub use crate::earth;
+}
+
+fn main() {
+    crate::collider::moon::foo(); // ok!
+    crate::collider::earth::foo(); // ok!
+}
+```