{"ast_node_type":"function","tokens":[{"end":85,"kind":"keyword","start":0,"text":"fn"}]}
    fn do_check(&self, fcx: &FnCtxt<'a, 'tcx>) -> Result<CastKind, CastError<'tcx>> {
    /// directly. coercion-cast is handled in check instead of here.
        use rustc_middle::ty::cast::CastTy::*;