我正在编写一些c ++模板代码来替换当前源中的if-else条件.在这里,我基于两个条件派生Helper数据类型,1.isAdvice 2. SimpleOrComplex
见下面的模板代码:
template<bool isAdvice, class SH, class CH>
class IfThenElse;
template<class SH, class CH>
class IfThenElse<true, SH, CH>
{
public:
typedef SH Helper;
};
template<class SH, class CH>
class IfThenElse<false, SH, CH>
{
public:
typedef CH Helper;
};
template <bool isAdvice, bool SimpleOrComplex>
class DeriveHelper
{
public:
typedef typename IfThenElse<isAdvice,
IfThenElse<SimpleOrComplex, SimpleHelper, ComplexHelper>::Helper,
IfThenElse<SimpleOrComplex, SimpleNoAdvHelper, ComplexNoAdvHelper>::Helper>::Helper DerivedHelper;
};
但是,在编译时获取此错误:
template.cpp:135: error: type/value mismatch at argument 2 in template parameter list for 'template<bool isTradeAdvice, class SH, class GH> …