Ability to return custom errors

[CowBoy4mH3LL]

Say I have a custom error SError{message:String} and I implement From<std:io:Error> on it.
Now, from a function, say, fn(&self) -> Result<(),SError> in an rtc::remote labelled trait, I get an std:io:error as a result of calling await on some other async function.
Even if I have implemented the From cast from Error to SError, it does not seem to be able to cast between the output Result forms.
Any idea why?

[surban]

Your custom error type must be serializable and it must implement From<CallError>.

For example:

// Custom error type that can convert from CallError.
#[derive(Debug, serde::Serialize, serde::Deserialize)]
pub enum IncreaseError {
    Overflow,
    Call(CallError),
}

impl From<CallError> for IncreaseError {
    fn from(err: CallError) -> Self {
        Self::Call(err)
    }
}