[英]c++ static methods and inheritance in templates with overloading
It's my first post here, I have looked for an answer for days, so I have ask. 这是我在这里的第一篇文章,几天来我一直在寻找答案,所以我要提问。 It is a complex construction. 这是一个复杂的结构。 I embed SpiderMonkey javascript engine in an Illustrator plugin. 我将SpiderMonkey JavaScript引擎嵌入到Illustrator插件中。 Illustrator has a complicate and sometimes inconsistent API. Illustrator具有复杂的API,有时甚至不一致。 In this case I have to call a method having a short type as parameter: 在这种情况下,我必须调用一个具有短类型作为参数的方法:
namespace ai
{
...
typedef signed short int16;
...
};
The method is referred as a pointer in a struct: 该方法在结构中称为指针:
struct AIDocumentSuite {
...
AIAPI AIErr (*GetDocumentRulerUnits) ( ai::int16 *units );
...
};
But, an enum is the source of the parameter: 但是,枚举是参数的来源:
enum AIDocumentRulerUnitValue {
kUnknownUnits = 0,
/** inches */
kInchesUnits,
/** centimeters */
kCentimetersUnits,
/** points */
kPointsUnits,
/** picas */
kPicasUnits,
/** millimeters */
kMillimetersUnits,
/** pixels */
kPixelsUnits,
/** Q units */
kQUnits
};
I have wrapped all these in classes in order to have javascript objects managed by SpiderMonkey. 我将所有这些包装在类中,以使SpiderMonkey管理javascript对象。 I have the following working call somewhere in the code (a bit simplified, cleaned up of tests an verifications): 我在代码中的某个地方有以下工作调用(有点简化,清理了测试和验证):
ai::int16 aiDocumentRulerUnitValue;
AIErr aiErr = sAIDocument->GetDocumentRulerUnits(&aiDocumentRulerUnitValue);
...
if (!jsAIDocumentRulerUnitValue::FromAIObject<jsAIDocumentRulerUnitValue>(cx, &aiDocumentRulerUnitValue, value))
return false;
...
jsProperty::SetProperty(cx, &obj, "value", value, true);
...
My issue is FromAIObject. 我的问题是FromAIObject。
I have a template base class: 我有一个模板基类:
template<typename T> class jsBaseDataClass : public jsBaseClass
{
public:
...
template <typename jsT> static bool FromAIObject(JSContext *cx, T* aiObj, JSObject*& obj)
{
...
return true;
}
}
and a derived class: 和派生类:
class jsAIDocumentRulerUnitValue : public jsBaseDataClass<AIDocumentRulerUnitValue>
{
public:
...
template <typename jsT> static bool FromAIObject(JSContext *cx, ai::int16* aiint16, JSObject*& obj)
{
AIDocumentRulerUnitValue aiDocumentRulerUnitValue = static_cast<AIDocumentRulerUnitValue>(*aiint16);
return jsEnumDataClass<jsBaseClass>::FromAIObject<jsAIDocumentRulerUnitValue>(cx, &aiDocumentRulerUnitValue, obj);
}
...
}
Now, the issue: if I write in the latter one: 现在的问题是:如果我写后者:
jsAIDocumentRulerUnitValue::FromAIObject<jsAIDocumentRulerUnitValue>(cx, &aiDocumentRulerUnitValue, obj);
it will try to call the method in the derived class (with the parameter of type ai::int16 = signed short). 它将尝试在派生类中调用方法(参数类型为ai :: int16 = signed short)。
If the method in the derived class wouldn't exist, it will call the method from the parent class, regardless the type of the second parameter. 如果派生类中的方法不存在,则它将从父类中调用该方法,而不管第二个参数的类型如何。
I wish to be able to look for the suitable method based on its parameters. 我希望能够根据其参数寻找合适的方法。 This would make me having a copy in each derived class of both methods (if necessary, or at least a copy of the default one). 这将使我在两种方法的每个派生类中都有一个副本(如有必要,或者至少是默认方法的一个副本)。
What am I doing wrong or how could I make them behave as in non static method overloading with inheritance? 我在做错什么,或者如何使它们的行为像在继承的非静态方法重载中一样?
Thank you. 谢谢。
You are doing nothing wrong. 你什么都没做错。 Your question looks like a duplicate of stack overflow: inheritance and method overloading 您的问题看起来像是堆栈溢出的重复:继承和方法重载
Overloaded methods get lost unless you using XXXX
除非您using XXXX
否则重载的方法会丢失
Do something like that. 做这样的事情。
class Base {
public:
static void method(std::string someParam);
}
class Derived : public Base {
public:
using Base::method;
static void method(int param);
}
The point is using the using
keyword for making base class's functions visible. 关键是使用using
关键字使基类的功能可见。
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