Method Evaluate

eval/eval/comprehension_step.cc:66–74

      : ExpressionStepBase(expr_id), accu_slot_(accu_slot) {}

  absl::Status Evaluate(ExecutionFrame* frame) const override {
    if (!frame->value_stack().HasEnough(2)) {
      return absl::Status(absl::StatusCode::kInternal, "Value stack underflow");
    }
    frame->value_stack().SwapAndPop(2, 1);
    frame->comprehension_slots().ClearSlot(accu_slot_);
    frame->iterator_stack().Pop();
    return absl::OkStatus();
  }

 private:
  const size_t accu_slot_;