Yes, you can simplify the match expression using the From or Into traits, or by leveraging the yaml-rust library's From implementations for basic types. However, in this case, since PrefValue is a custom enum and Yaml is from the yaml-rust crate, you can use the Into trait if PrefValue implements it for Yaml.

But looking at the provided links and the code, there is no direct From or Into implementation between PrefValue and Yaml in the mozprofile or yaml-rust crates. Therefore, the simplest way to achieve this is to use a map operation or a helper function to convert PrefValue to Yaml.

Simplified Version Using a Helper Function

If you frequently convert PrefValue to Yaml, you can define a helper function or a trait implementation:

impl From<PrefValue> for Yaml {
    fn from(value: PrefValue) -> Self {
        match value {
            PrefValue::Bool(b) => Yaml::Boolean(b),
            PrefValue::Int(i) => Yaml::Integer(i),
            PrefValue::String(s) => Yaml::String(s),
        }
    }
}

Now, you can use it like this:

let yaml_value: Yaml = pref_value.into();
// or
let yaml_value = Yaml::from(pref_value);

Simplified Version Using a Macro

If you want to avoid writing a match block every time, you could also use a macro:

macro_rules! to_yaml {
    ($value:expr) => {
        match $value {
            PrefValue::Bool(b) => Yaml::Boolean(b),
            PrefValue::Int(i) => Yaml::Integer(i),
            PrefValue::String(s) => Yaml::String(s),
        }
    };
}

let yaml_value = to_yaml!(pref_value);

Simplified Version Using a Method

If you can modify the PrefValue enum, you could add a method to it:

impl PrefValue {
    fn to_yaml(&self) -> Yaml {
        match self {
            PrefValue::Bool(b) => Yaml::Boolean(*b),
            PrefValue::Int(i) => Yaml::Integer(*i),
            PrefValue::String(s) => Yaml::String(s.clone()),
        }
    }
}

let yaml_value = pref_value.to_yaml();

Which One to Choose?

• Use From/Into if you want idiomatic Rust and plan to use this conversion often.
• Use a macro if you want a concise syntax and don't want to modify the PrefValue enum.
• Use a method if you can modify the PrefValue enum and want a clean, object-oriented approach.