{"ast_node_type":"variable","tokens":[{"end":57,"kind":"keyword","start":0,"text":"let"}]}
        let a_val = bx.gcc_int_cast(a_val, new_int_type);
        // TODO: we probably need to use gcc_int_cast instead.
        let b_val = bx.context.new_vector_access(None, b, index).to_rvalue();