Question

for some reason this code throws an error

// map<int, AnItem> roomlist;
// map<string, long> rinventory

map<int, AnItem>::iterator it;

for ( it = roomlist[roomno].rinventory.beg/in(); it != roomlist[roomno].rinventory.end(); it++ )    {

        if( (*it).second.name == "Stock" )
            tmpitem.append( strmug );
    }

The if statment throws the error. It’s really not that complex and I would think I could handle this. So… roomlist is a map, roomno is an integer and rinventory is a map

class AnThing   {

public:
    AnThing();              // constructor
    string name;                // name reference
    int gtid;               // Thing ID
    string lcname;              // name in lowercase
    string m_name;
};

class AnItem : public AnThing   {

public:

    ItemType m_type;
    int imin;
    int imax;
    int ispeed;
    long unsigned iprice;
    unsigned int ecoin;
    GAttributes m_attributes;

    AnItem(); //Constructs an item with "invalid" values

    int& Min(); // Returns the min attribute
    int& Max(); // Returns the max attribute
    int& Speed(); // Returns the speed attribute

};

Thanks in advance! I will append the errors I get below (there are two of them)

c:\ucdhb2\gaia\logonserver\v6\gaiaserver.cpp(812) : error C2679:
binary ‘=’ : no operator found which takes a right-hand operand of
type ‘std::_Tree<_Traits>::iterator’ (or there is no acceptable
conversion) 1> with 1> [ 1>
_Traits=std::_Tmap_traits,std::allocator>,false> 1> ] 1> c:\program
files\microsoft visual studio 9.0\vc\include\xtree(498): could be
‘std::_Tree<_Traits>::iterator
&std::_Tree<_Traits>::iterator::operator =(const
std::_Tree<_Traits>::iterator &)’ 1> with 1> [ 1>
_Traits=std::_Tmap_traits,std::allocator>,false> 1> ] 1> while trying to match the
argument list ‘(std::_Tree<_Traits>::iterator,
std::_Tree<_Traits>::iterator)’ 1> with 1> [ 1>
_Traits=std::_Tmap_traits,std::allocator>,false> 1> ] 1> and 1> [ 1>
_Traits=std::_Tmap_traits,std::allocator>,false> 1> ]
1>c:\ucdhb2\gaia\logonserver\v6\gaiaserver.cpp(812) : error C2678:
binary ‘!=’ : no operator found which takes a left-hand operand of
type ‘std::_Tree<_Traits>::iterator’ (or there is no acceptable
conversion) 1> with 1> [ 1>
_Traits=std::_Tmap_traits,std::allocator>,false> 1> ] 1> c:\program files\microsoft
sdks\windows\v6.0a\include\guiddef.h(197): could be ‘int operator
!=(const GUID &,const GUID &)’ 1> c:\program files\microsoft
visual studio 9.0\vc\include\xtree(314): or ‘bool
std::_Tree<_Traits>::const_iterator::operator !=(const
std::_Tree<_Traits>::const_iterator &) const’ 1> with 1>
[ 1>
_Traits=std::_Tmap_traits,std::allocator>,false> 1> ] 1> while trying to match the
argument list ‘(std::_Tree<_Traits>::iterator,
std::_Tree<_Traits>::iterator)’ 1> with 1> [ 1>
_Traits=std::_Tmap_traits,std::allocator>,false> 1> ] 1> and 1> [ 1>
_Traits=std::_Tmap_traits,std::allocator>,false> 1> ]

Answer 1

Your iterator

map<int, AnItem>::iterator it;

needs to be of type

map<string, long>::iterator it;

based on your comment (i.e. you are iterating over rinventory, not roomlist).