Derefence pointer to object from vector in C++

Question

I have a class that is inserting nodes with these functions:

In Node.h

class Node
{
public:
...
void insertChild(Node *child);
vector<Node *> children();
vector<Node *> _children;
};

In Node.cpp

void Node::insertChild(Node *child){
    _children.push_back(child);
}

vector<Node *> Node::children(){
return _children;
}

In Trie.h

class Trie
{
public:
Node *getRoot() const;
Node *root;
void addWord(string prefix);
}

In Trie.cpp

Trie::Trie()
{
root = new Node();
}

Node *Trie::getRoot() const
{
return root;
}

void Trie::addWord(string prefix){
    Node *current = root;

    if(prefix.length() == 0)
    {
        current->setTypeMarker(DAT_NODE);
        return;
    }

    for(int i = 0; i < prefix.length(); i++){
        Node *child = current->lookupChild(prefix[i]);
        if(child != NULL)
        {
            current = child;
        }
        else
        {
            Node *tmp = new Node();
            tmp->setContent(prefix[i]);
            current->insertChild(tmp);
            current = tmp;
        }
        if(i == prefix.length()-1)
            current->setTypeMarker(DAT_NODE);
     }
}

In another class, I want to iterate over _children so I have

In OtherClass.h

class OtherClass
{
public:
Trie *trie;
void addWords(string word)
void someFunction()
}

In OtherClass.cpp

OtherClass::OtherClass()
{
tree = new Trie();
}

void OtherClass::addWords(string word)
{
tree->addWord(word);
}

void OtherClass::someFunction()
{
Node *root = tree->getRoot();
    for(std::vector<Node *>::iterator it = root->children().begin(); it != root->children().end(); it++) {
        Node * test = *it;
    }
}

However, when I run this, test is nil. I can look at root and see that children contains my Nodes, but how come I can't de-reference them in the vector iterator? children() is my getter for _children

Answer 1

May be your getter return std::vector by value not by the reference?

The getter should look like this:

std::vector<Node*>& Node::children()
{
    return _children;
}

or for const version like this:

const std::vector<Node*>& Node::children() const
{
    return _children;
}