problem with const reference return and STL vectors

I am having issues with the following snippet of code

    string const& symbol::at(int index) const {
    assert(index<symbol_data.vector::size());
    return symbol_data.vector::at(index);
    }

Here, symbol_data is a private member of the class and is a vector

::at is a member function in the symbol class that I have defined.

When I try compiling this code, I get the following error messsage:

    error: ‘template<class _Tp, class _Alloc> class std::vector’ used without template parameters

However, there is no error if I change the function prototype to

    string symbol::at(int index) {...}

Does anybody know how I can get STL vectors to work properly 开发者_Go百科with const references?

Your code as I'm writing this:

string const& symbol::at(int index) const {
    assert(index<symbol_data.vector::size());
    return symbol_data.vector::at(index);
    }

Instead of symbol_data.vector:: write just symbol_data..

Cheers & hth.,

I can't reproduce your problem; the following compiles and works fine on VS2010 express.

#include <cassert>
#include <iostream>
#include <string>
#include <vector>

class symbol 
{
  std::vector<std::string> symbol_data;

public:
  symbol()
  {
    symbol_data.push_back( "Str1" );
    symbol_data.push_back( "Str2" );
  }

  std::string const& at( int index ) const 
  {
    assert( index < symbol_data.vector::size() );

    return symbol_data.vector::at( index );
  }
};

int main()
{
  symbol s;

  std::cout << s.at( 0 ) << std::endl;
  std::cin.get();

  return 0;
}