Error code E0446
A private type was used in a public type signature.
Erroneous code example:
#![deny(private_in_public)] struct Bar(u32); mod foo { use crate::Bar; pub fn bar() -> Bar { // error: private type in public interface Bar(0) } } fn main() {}
There are two ways to solve this error. The first is to make the public type signature only public to a module that also has access to the private type. This is done by using pub(crate) or pub(in crate::my_mod::etc) Example:
struct Bar(u32); mod foo { use crate::Bar; pub(crate) fn bar() -> Bar { // only public to crate root Bar(0) } } fn main() {}
The other way to solve this error is to make the private type public. Example:
pub struct Bar(u32); // we set the Bar type public mod foo { use crate::Bar; pub fn bar() -> Bar { // ok! Bar(0) } } fn main() {}