I'm implementing an AVL-tree as part of a library and can't figure out whether it is CppUnit, NetBeans 8, my C++ skills (templates) or something else that is the problem, but the code compiles as a static library but when used together with CppUnit or a standalone application I get undefined reference to MyProject::Utilities::AVLTree<int, char>::function
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I've reduced the code as much as possible while still maintaining the same error.
AVLTree.h
namespace MyProject {
namespace Utilities {
template <typename KeyType, typename ValueType> class AVLTree {
public:
AVLTree();
AVLTree(const MyProject::Utilities::AVLTree<KeyType, ValueType>& orig);
virtual ~AVLTree();
bool hasRoot() const;
MyProject::Utilities::AVLNode<KeyType, ValueType>* getRoot() const;
protected:
void setRoot(MyProject::Utilities::AVLNode<KeyType, ValueType>* _node);
private:
MyProject::Utilities::AVLNode<KeyType, ValueType>* _root;
unsigned int _size;
};
};
};
AVLTree.cpp
template <typename KeyType, typename ValueType> MyProject::Utilities::AVLTree<KeyType, ValueType>::AVLTree() {
this->setRoot(NULL);
this->_size = 0;
}
template <typename KeyType, typename ValueType> MyProject::Utilities::AVLTree<KeyType, ValueType>::AVLTree(const MyProject::Utilities::AVLTree<KeyType, ValueType>& orig) {
this->setRoot(orig.getRoot());
this->_size = orig.size();
}
template <typename KeyType, typename ValueType> MyProject::Utilities::AVLTree<KeyType, ValueType>::~AVLTree() {
// this->clear();
}
template <typename KeyType, typename ValueType> void MyProject::Utilities::AVLTree<KeyType, ValueType>::setRoot(MyProject::Utilities::AVLNode<KeyType, ValueType>* _root) {
this->_root = _root;
}
template <typename KeyType, typename ValueType> bool MyProject::Utilities::AVLTree<KeyType, ValueType>::hasRoot() const {
return this->getRoot() != NULL;
}
template <typename KeyType, typename ValueType> MyProject::Utilities::AVLNode<KeyType, ValueType>* MyProject::Utilities::AVLTree<KeyType, ValueType>::getRoot() const {
return this->_root;
}
main.cpp
#include <cstdlib>
#include "AVLTree.h"
int main(int argc, char** argv) {
MyProject::Utilities::AVLTree<int, char> instance;
for (unsigned int i = 0; i < 20; ++i) {
instance.hasRoot();
// instance.insert(i, (char) (65 + i));
}
//instance.graphviz("./test.dot");
return 0;
}
The following error is returned by Netbeans 8 when attempting to build cppapplication_1
g++ -c -g -I../../Documents/MyProject/src/header -MMD -MP -MF "build/Debug/GNU-Linux-x86/main.o.d" -o build/Debug/GNU-Linux-x86/main.o main.cpp
mkdir -p dist/Debug/GNU-Linux-x86
g++ -o dist/Debug/GNU-Linux-x86/cppapplication_1 build/Debug/GNU-Linux-x86/main.o -L../../Documents/MyProject/dist/Debug/GNU-Linux-x86 -lmyproject
build/Debug/GNU-Linux-x86/main.o: In function `main':
/home/.../CppApplication_1/main.cpp:6: undefined reference to `MyProject::Utilities::AVLTree<int, char>::AVLTree()'
/home/.../CppApplication_1/main.cpp:8: undefined reference to `MyProject::Utilities::AVLTree<int, char>::hasRoot() const'
/home/.../CppApplication_1/main.cpp:12: undefined reference to `MyProject::Utilities::AVLTree<int, char>::~AVLTree()'
/home/.../CppApplication_1/main.cpp:12: undefined reference to `MyProject::Utilities::AVLTree<int, char>::~AVLTree()'
collect2: error: ld returned 1 exit status
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The code below produces about 100 errors of varying content... I don't mean to be daft but for the life of me I can't figure out what is wrong, nor can I find a working example or tutorial to work with...
src/header/AVLTree.h:16:23: error: declaration of ‘class KeyType’
template <typename KeyType, typename ValueType> AVLTree();
src/header/AVLTree.h:14:19: error: shadows template parm ‘class KeyType’
template <typename KeyType, typename ValueType> class AVLTree {
src/header/AVLTree.h:16:41: error: declaration of ‘class ValueType’
template <typename KeyType, typename ValueType> AVLTree();
src/header/AVLTree.h:14:37: error: shadows template parm ‘class ValueType’
template <typename KeyType, typename ValueType> class AVLTree {
In file included from src/AVLTree.cpp:1:0:
src/header/AVLTree.h:18:23: error: declaration of ‘class KeyType’
template <typename KeyType, typename ValueType> virtual ~AVLTree();
AVLTree.h
namespace MyProject {
namespace Utilities {
template <typename KeyType, typename ValueType> class AVLTree {
public:
template <typename KeyType, typename ValueType> AVLTree();
template <typename KeyType, typename ValueType> AVLTree(const MyProject::Utilities::AVLTree<KeyType, ValueType>& orig);
template <typename KeyType, typename ValueType> virtual ~AVLTree();
template <typename KeyType, typename ValueType> bool hasRoot() const;
template <typename KeyType, typename ValueType> MyProject::Utilities::AVLNode<KeyType, ValueType>* getRoot() const;
protected:
void setRoot(MyProject::Utilities::AVLNode<KeyType, ValueType>* _node);
private:
MyProject::Utilities::AVLNode<KeyType, ValueType>* _root;
};
};
};
AVLTree.cpp (with types specified)
MyProject::Utilities::AVLTree<KeyType, ValueType>::AVLTree() {
this->setRoot(NULL);
}
MyProject::Utilities::AVLTree<KeyType, ValueType>::AVLTree(const MyProject::Utilities::AVLTree<KeyType, ValueType>& orig) {
this->setRoot(orig.getRoot());
// this->_size = orig.size();
}
MyProject::Utilities::AVLTree<KeyType, ValueType>::~AVLTree() {
// this->clear();
}
void MyProject::Utilities::AVLTree<KeyType, ValueType>::setRoot(MyProject::Utilities::AVLNode<KeyType, ValueType>* _root) {
this->_root = _root;
}
bool MyProject::Utilities::AVLTree<KeyType, ValueType>::hasRoot() const {
return this->getRoot() != NULL;
}
MyProject::Utilities::AVLNode<KeyType, ValueType>* MyProject::Utilities::AVLTree<KeyType, ValueType>::getRoot() const {
return this->_root;
}
AVLTree.cpp (with types unspecified)
MyProject::Utilities::AVLTree::AVLTree() {
this->setRoot(NULL);
}
MyProject::Utilities::AVLTree::AVLTree(const MyProject::Utilities::AVLTree& orig) {
this->setRoot(orig.getRoot());
// this->_size = orig.size();
}
MyProject::Utilities::AVLTree::~AVLTree() {
// this->clear();
}
void MyProject::Utilities::AVLTree::setRoot(MyProject::Utilities::AVLNode<KeyType, ValueType>* _root) {
this->_root = _root;
}
bool MyProject::Utilities::AVLTree::hasRoot() const {
return this->getRoot() != NULL;
}
MyProject::Utilities::AVLNode<KeyType, ValueType>* MyProject::Utilities::AVLTree::getRoot() const {
return this->_root;
}