42 lines
669 B
C++
42 lines
669 B
C++
#ifndef ISDERIVEDFROM_H_
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#define ISDERIVEDFROM_H_
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template<typename D, typename B>
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class IsDerivedFrom {
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class No {
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};
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class Yes {
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No no[3];
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};
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static Yes Test(B*); // declared, but not defined
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static No Test(... ); // declared, but not defined
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public:
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enum {
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Is = sizeof(Test(static_cast<D*>(0))) == sizeof(Yes)
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};
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};
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template<typename, typename>
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struct is_same {
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static bool const value = false;
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};
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template<typename A>
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struct is_same<A, A> {
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static bool const value = true;
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};
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template<bool C, typename T = void>
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struct enable_if {
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typedef T type;
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};
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template<typename T>
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struct enable_if<false, T> { };
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#endif /* ISDERIVEDFROM_H_ */
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