Question

I have been having this problem for awhile with my code, looking for my mistake I can’t see it. I have a map, map I am mapping keywords to the values.
My problem is sometimes when inserting keyword = “Blue” the value is inserting into the Key for “Red”.
So instead of,
Key: Red, Value: obj1, obj2
Key: Blue, Value: obj3, obj4
I get,
Key: Red, Value: obj1, obj2, obj4 (obj4 should be keyed to Blue)
Key: Blue, Value: obj3

Not sure what it can be since the same version of the code works for other maps that I have, they just don’t have as many Keys.

addKeywordsForObject(const Object* const object, int nKeywords, ...)
{
va_list     keywords;
char        *keyword;

va_start(keywords, nKeywords);
for (int i = 0; i < nKeywords; i++) {
    keyword = va_arg(keywords, char*);

    if(objectToKeywordMap.find(keyword) == objectToKeywordMap.end()) {  
        keywordObject = new ObjectSet();
        keywordObject->insert(const_cast<Object* const>(object));
        objectToKeywordMap.emplace(StringToObjectSetMap::value_type(keyword,keywordObject));
    }
    else {
        keywordObject->insert(const_cast<Object* const>(object));   
        objectToKeywordMap.emplace(StringToObjectSetMap::value_type(keyword,keywordObject));
    }
}
va_end(keywords);
}  

Answer 1

I see no declaration for keywordObject, so I shall assume it’s a global. The case of adding a new object to a keyword which is already present is dealt with in the else. What is the value of keywordObject in this case? Who sets it?

There are a number of other problems with this code, some mentioned in other answers and comments.

• missing return type for addKeywordsForObject
• possible usage of char* as a map key which requires special handling (not clear, because you haven’t shown the declaration of StringToObjectSetMap)
• a function which takes a variable number of parameters by using ellipsis (almost never a good idea in C++)
• use of a global variable where a local variable is appropriate