Trait ConfigLoaderTrait

pub trait ConfigLoaderTrait<S, T, D> {
    type RetType;
    type Error;

    // Required method
    fn make_from(
        config: &mut S,
        cfg: T,
        data: D,
    ) -> Result<Self::RetType, Self::Error>;
}

A trait which is implemented by the structures which are planned to translate the configuration structures into pre-prepared instances. For example, there is a CfgServer which is deserialized from the /etc/myprogram/server.shm which contains generic fields like bind address encoded as String and may contain errors. A structure ConfigServer which parses this data to IpAddr instance. It implements this trait in order to be attached to CfgServer and called to fill its fields from CfgServer.

Required Associated Types

type RetType

A return type which is returned after calling make_from.

type Error

An error type returned in case of i.e validation fail.

Required Methods

fn make_from( config: &mut S, cfg: T, data: D, ) -> Result<Self::RetType, Self::Error>

This function is called to build a ‘Self::RetType’ as a result.

The following generics should be provided:

• S - an instance which can be reused to open another file. Usually a structure which holds the ConfigLoader instance.

• T - a structure which holds the deserialized config file to be processed.

• D - an additional arguments to be passed to next. Usually it is () when there is nothing to pass. However, it it is required to pass something to the next stage, this generic argument can be used.

Returns

A Result is returned with the:

• [Result::Ok()] is returned with inner type Self::RetType which describes the result.

• [Result::Err()] is returned with the error description.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementors