How to combine OneOrMany with HashMap?

[mainrs]

I basically want this:

#[serde_as]
pub struct A {
    #[serde_as(as = "HashMap<String, OneOrMany<_>>")]
    pub keys: HashMap<String, Vec<OtherStruct>>,
}

I get an error:

the trait bound `HashMap<std::string::String, OneOrMany<Same>>: DeserializeAs<'_, _>` is not satisfied
   -->...
    |
72  | #[serde_as]
    | ^^^^^^^^^^^ the trait `DeserializeAs<'_, _>` is not implemented for `HashMap<std::string::String, OneOrMany<Same>>`

[jonasbb]

I think the issue is your use of String in the attribute. Try replacing it with a _ like
#[serde_as(as = "HashMap<_, OneOrMany<_>>")]. Unfortunately if you want to use the normal serialization behavior of a type you have to use _ since just writing the type will lead to the error you report.