help with templates please

[GrahamLabdon]

Hi
I have the following code defining a template class

template<class T>
	class TemplateClass
	{
	public:
		TemplateClass();
		virtual ~TemplateClass() {}
		void add (T key, QString value);
		void get(QStringList &theStrings) const;
 
	private:
		QMap<T,QString> m_strings;
 
	};
 
template<class T> TemplateClass<T>::TemplateClass()
{
 
}
 
template<class T> void TemplateClass<T>::add (T key, QString value)
{
	m_strings[key] = value;
}
 
template<class T> void TemplateClass<T>::getComboBoxStrings(QStringList &theStrings) const
{
	QMap<T,QString>::iterator it;

template<class T>
	class TemplateClass
	{
	public:
		TemplateClass();
		virtual ~TemplateClass() {}
		void add (T key, QString value);
		void get(QStringList &theStrings) const;

	private:
		QMap<T,QString> m_strings;

	};

template<class T> TemplateClass<T>::TemplateClass()
{

}

template<class T> void TemplateClass<T>::add (T key, QString value)
{
	m_strings[key] = value;
}

template<class T> void TemplateClass<T>::getComboBoxStrings(QStringList &theStrings) const
{
	QMap<T,QString>::iterator it;

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When compiled I get the following error regarding the declaration of the iterator

MyClass.h: In member function 'void TemplateClass<T>::getComboBoxStrings(QStringList&) const':
MyClass.h:74: error: expected ';' before 'it'

MyClass.h: In member function 'void TemplateClass<T>::getComboBoxStrings(QStringList&) const':
MyClass.h:74: error: expected ';' before 'it'

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Could someone tell me why this is and error

[stampede]

QMap<T,QString>::iterator it;

QMap<T,QString>::iterator it;

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Because compiler does not know that "iterator" is a typename. You need to specify that:

typename QMap<T,QString>::iterator it;

typename QMap<T,QString>::iterator it;

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----------------
I see that g++ (v 4.5.2) produces a nice message:

template <class C> class Test{
	public:
		void fun();
};
 
template<class C> void Test<C>::fun(){
	C::iterator it;
}
 
// error: need 'typename' before 'C:: iterator' because 'C' is a dependent scope

template <class C> class Test{
	public:
		void fun();
};

template<class C> void Test<C>::fun(){
	C::iterator it;
}

// error: need 'typename' before 'C:: iterator' because 'C' is a dependent scope

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[mcosta]

Use the typename keyword.

template<class T> void TemplateClass<T>::getComboBoxStrings(QStringList &theStrings) const
{
	typename QMap<T,QString>::const_iterator it;

template<class T> void TemplateClass<T>::getComboBoxStrings(QStringList &theStrings) const
{
	typename QMap<T,QString>::const_iterator it;

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When you use a "compile time unresolved class" (class defined by a template argument) you must suggest the compiler that this class has a type named "const_iterator"