Enum RunnerKind 

pub enum RunnerKind {
    R(RRunner),
    Python(PythonRunner),
}

A runner chosen for a lesson’s language.

A closed enum holding one concrete runner. Runner::execute returns impl Future (an RPITIT), so the trait is not object-safe and a runtime-chosen runner cannot be a Box<dyn Runner>; an enum is how we carry that choice instead. Consumers still depend on the Runner trait, not on these concrete variants — RunnerKind itself impls it, so run_checks takes impl Runner and never names RRunner/PythonRunner (§3.4). The match over it is exhaustive: adding a Language variant forces a new arm both here and in select_runner, so a language can never be silently dropped.

Variants

R(RRunner)

The R runner.

Python(PythonRunner)

The Python runner.

Trait Implementations

impl Clone for RunnerKind

fn clone(&self) -> RunnerKind

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for RunnerKind

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Runner for RunnerKind

async fn execute( &self, code: &str, checks: &[String], ) -> Result<ExecutionResult, RunnerError>

Execute code, returning its normalized ExecutionResult.