C++: Trouble with templates (C2064)
- by Rosarch
I'm having compiler errors, and I'm not sure why. What am I doing wrong here:
Hangman.cpp:
set<char> Hangman::incorrectGuesses()
{
// Hangman line 103
return Utils::findAll_if<char>(guesses.begin(), guesses.end(), &Hangman::isIncorrectGuess);
}
bool Hangman::isIncorrectGuess(char c)
{
return correctAnswer.find(c) == string::npos;
}
Utils.h:
namespace Utils
{
void PrintLine(const string& line, int tabLevel = 0);
string getTabs(int tabLevel);
template<class result_t, class Predicate>
std::set<result_t> findAll_if(typename std::set<result_t>::iterator begin, typename std::set<result_t>::iterator end, Predicate pred)
{
std::set<result_t> result;
// utils line 16
return detail::findAll_if_rec<result_t>(begin, end, pred, result);
}
}
namespace detail
{
template<class result_t, class Predicate>
std::set<result_t> findAll_if_rec(typename std::set<result_t>::iterator begin, typename std::set<result_t>::iterator end, Predicate pred, std::set<result_t> result)
{
// utils line 25
typename std::set<result_t>::iterator nextResultElem = find_if(begin, end, pred);
if (nextResultElem == end)
{
return result;
}
result.insert(*nextResultElem);
return findAll_if_rec(++nextResultElem, end, pred, result);
}
}
This produces the following compiler errors:
algorithm(83): error C2064: term does not evaluate to a function taking 1 arguments
algorithm(95) : see reference to function template instantiation '_InIt std::_Find_if<std::_Tree_unchecked_const_iterator<_Mytree>,_Pr>(_InIt,_InIt,_Pr)' being compiled
1> with
1> [
1> _InIt=std::_Tree_unchecked_const_iterator<std::_Tree_val<std::_Tset_traits<char,std::less<char>,std::allocator<char>,false>>>,
1> _Mytree=std::_Tree_val<std::_Tset_traits<char,std::less<char>,std::allocator<char>,false>>,
1> _Pr=bool (__thiscall Hangman::* )(char)
1> ]
utils.h(25) : see reference to function template instantiation '_InIt std::find_if<std::_Tree_const_iterator<_Mytree>,Predicate>(_InIt,_InIt,_Pr)' being compiled
1> with
1> [
1> _InIt=std::_Tree_const_iterator<std::_Tree_val<std::_Tset_traits<char,std::less<char>,std::allocator<char>,false>>>,
1> _Mytree=std::_Tree_val<std::_Tset_traits<char,std::less<char>,std::allocator<char>,false>>,
1> Predicate=bool (__thiscall Hangman::* )(char),
1> _Pr=bool (__thiscall Hangman::* )(char)
1> ]
utils.h(16) : see reference to function template instantiation 'std::set<_Kty> detail::findAll_if_rec<result_t,Predicate>(std::_Tree_const_iterator<_Mytree>,std::_Tree_const_iterator<_Mytree>,Predicate,std::set<_Kty>)' being compiled
1> with
1> [
1> _Kty=char,
1> result_t=char,
1> Predicate=bool (__thiscall Hangman::* )(char),
1> _Mytree=std::_Tree_val<std::_Tset_traits<char,std::less<char>,std::allocator<char>,false>>
1> ]
hangman.cpp(103) : see reference to function template instantiation 'std::set<_Kty> Utils::findAll_if<char,bool(__thiscall Hangman::* )(char)>(std::_Tree_const_iterator<_Mytree>,std::_Tree_const_iterator<_Mytree>,Predicate)' being compiled
1> with
1> [
1> _Kty=char,
1> _Mytree=std::_Tree_val<std::_Tset_traits<char,std::less<char>,std::allocator<char>,false>>,
1> Predicate=bool (__thiscall Hangman::* )(char)
1> ]
