{"ast_node_type":"other","tokens":[{"end":77,"kind":"keyword","start":0,"text":"hir::CallableKind::FnImpl(fn_trait)"}]}
        hir::CallableKind::FnImpl(fn_trait) => match callable.ty().as_adt() {
        hir::CallableKind::FnPtr => format_to!(res.signature, "fn"),
            // FIXME: Render docs of the concrete trait impl function