Specman e: "keep type .. is a" 无法细化字段类型

Question

我的验证环境中有下一段代码：

// seq_file.e
extend SPECIFIC_TYPE sequence {
    keep type driver is a SPECIFIC_TYPE sequence_driver;
    event some_event is @driver.as_a(SPECIFIC_TYPE sequence_driver).some_event;
};

extend SPECIFIC_TYPE SEQ_NAME sequence {
   body()@driver.clock is only {
      var foo := driver.specific_type_field;
   };
};

请注意，由于 keep type driver is a..，driver 无需在 var foo..

行中进行转换

BUT，keep type driver is a.. 不影响 some_event，即如果从行中删除 as_a 转换，则有编译错误显示 'driver' does not have 'some_event' though its subtype do. use driver.as_a(SPECIFIC_TYPE sequence_driver).

为什么 keep type driver is a.. 无法在 some_event.. 行中转换 driver？

感谢您的帮助

Answer 1

您的观察是正确的：字段访问（和方法调用）考虑了类型约束，但事件采样未考虑类型约束。这是一个限制，可能会在即将发布的版本中删除。我建议联系官方 Specman 支持以获取有关计划的确切信息。

Specman e: "keep type .. is a" 无法细化字段类型

Specman e: "keep type .. is a" fails to refine the type of a field

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