How do you return a vector iterator from a variable in a template class?
I'm trying to return an iterator for a vector in a templated class (I'm not sure if this matters, but I read I could, so I thought I mentioned it). The problem is I get an error that C ++ doesn't support default-int when I try to do this. I looked online and from what I see in the forums and explanations I don't think I'm that far, it just won't compile.
template<class T>
class Table
{
public:
...
vector<shared_ptr<vector<T>>>::iterator GetRowIterator();
//vector<shared_ptr<vector<CellValueType> > >::const_iterator GetRowIterator();
...
protected:
vector<shared_ptr<vector<CellValueType> > > data; //outside vector is rows, inside vector is columns
...
};
vector<shared_ptr<vector<T> > >::const_iterator Table<T>::GetRowIterator()
{
return data.begin();
}
I am getting the following errors:
error C2146: syntax error : missing ';' before identifier 'GetRowIterator'
error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
Edit:
Changed the end angle brackets so they are not that close together - same error.
Any thoughts on why this is happening?
As always, thanks for the advice / help in advance!
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Also, remember to use typename when declaring the type of a template's return type:
typename vector< shared_ptr< vector< T > > >::iterator GetRowIterator();
and method definition
typename vector< shared_ptr< vector< T > > >::const_iterator Table<T>::GetRowIterator()
{
return data.begin();
}
Note also that when defining a template class method outside of the class definition, you need to use the template keyword:
template <class T> typename vector< shared_ptr< vector< T > > >::const_iterator Table<T>::GetRowIterator()
{
return data.begin();
}
So the compiler can know what T.
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This part is here:
vector<shared_ptr<vector<T>>>
This is a C ++ syntax problem that you cannot install -> together.
vector<shared_ptr<vector<T> > >
This is the problem that the new standard addresses.
Since the lexer is the first stage of the compiler, it sees →> as a left shift operator followed by>. This way you get syntax errors in your code. To fix this problem, you just need to add a space between> when closing templates.
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