C++: error C2143: syntax error : missing ';' before '<' - c++

Question

#include "stdafx.h"
#include<vector>
template<class T, int capacity = 30>
class Stack {
public:
Stack(){
pool.reserve(capacity);
}
void clear(){
pool.clear;
}
void isEmpty(){
return pool.empty();
}
T& topEl(){
return pool.back();
}
T pop(){
T el = pool.back();
pool.pop_back();
return el;
}
void push(const T& el){
pool.push_back(el);
}
private:
vector<T> pool;
};
int _tmain(int argc, _TCHAR* argv[])
{
//Stack<int,30> test;
return 0;
}
Above is the code that I have written, which outlines a very generic vector implementation of stack. However,when I compiled it, I got the following errors from the compiler.
1>------ Rebuild All started: Project: Stack, Configuration: Debug Win32 ------
1> stdafx.cpp
1> Stack.cpp
1>c:\users\lxjhk\documents\visual studio 2013\projects\stack\stack\stack.cpp(31): error C2143: syntax error : missing ';' before '<'
1> c:\users\lxjhk\documents\visual studio 2013\projects\stack\stack\stack.cpp(32) : see reference to class template instantiation 'Stack<T,capacity>' being compiled
1>c:\users\lxjhk\documents\visual studio 2013\projects\stack\stack\stack.cpp(31): error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>c:\users\lxjhk\documents\visual studio 2013\projects\stack\stack\stack.cpp(31): error C2238: unexpected token(s) preceding ';'
========== Rebuild All: 0 succeeded, 1 failed, 0 skipped ==========
I really could not understand where went wrong and I have checked the code against my book multiple times but could not find any difference.

Answer 1

The vector<T> template class is defined in the std namespace. You shouldn't use a using namespace statement in a header, so instead you should prefix all STL types with std::
...
private:
std::vector<T> pool;
};
...
As an aside, assuming this isn't a homework exercise, have you seen std::stack<T>? ( http://www.cplusplus.com/reference/stack/stack/ )

Answer 2

void clear(){
pool.clear;
}
should be
void clear(){
pool.clear();
}
And since vector<T> is in namespace std, you should use
std::vector<T> pool;
in your class definition.