{"ast_node_type":"variable","tokens":[{"end":38,"kind":"keyword","start":0,"text":"let"}]}
        let var = self.new_type_var();
    pub(crate) fn normalize_projection_ty(&mut self, proj_ty: ProjectionTy) -> Ty {
        let alias_eq = AliasEq { alias: AliasTy::Projection(proj_ty), ty: var.clone() };