Method has_loop_step

common/expr.h:794–796

  ABSL_MUST_USE_RESULT std::unique_ptr<Expr> release_loop_condition();

  ABSL_MUST_USE_RESULT bool has_loop_step() const {
    return loop_step_ != nullptr;
  }

  ABSL_MUST_USE_RESULT const Expr& loop_step() const
      ABSL_ATTRIBUTE_LIFETIME_BOUND;