I'm attempting to have a derived class (normal template) that has a variable of a temp开发者_StackOverflowlate type that has as its template class parameter the type of a base class (normal template, same parameter as the derived class) of the derived class (the one with the variable). This makes VC++ incredibly angry at me, and I am incapable of calming its fury. Here's a quick example:
template<template<typename VT> class CT, typename VT> struct encapThing {};
template<typename VT> struct innocuousBase {};
template<typename VT> struct derivOfDoom : public innocuousBase<VT>
{
encapThing<innocuousBase, VT> ohgodhelp; //C3200
};
It will throw a C3200, saying it expected a class template. Now, I can see why this might be thinking there is a recursive loop of templates within templates, even if this isn't actually the case. How can I convince VC++ otherwise?
Unqualified use of innocuousBase
inside of derivOfDoom<>
is interpreted as innocuousBase<VT>
, much as unqualified use of derivOfDoom
in that context would be interpreted as derivOfDoom<VT>
. I don't remember offhand whether or not this is standard-conformant behavior, but the workaround is trivial: fully qualify innocuousBase
so the compiler knows you're referring to the innocuousBase
class template and not the innocuousBase<VT>
base class:
template<typename VT> struct derivOfDoom : innocuousBase<VT>
{
encapThing<::innocuousBase, VT> ohgodhelp;
};
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