Function determine_async

pub fn determine_async<'tcx>(
    tcx: TyCtxt<'tcx>,
    def_id: DefId,
    body: &Body<'tcx>,
) -> Option<(Instance<'tcx>, Location, AsyncType)>

Try to interpret this function as an async function.

If this is an async function it returns the Instance of the generator, the location where the generator is bound and the type of [Asyncness] which in this case is guaranteed to satisfy [Asyncness::is_async].