If I want to specialise just one method in a template, how do I do it?

Question

Say I have a templated class like

template <typename T> struct Node {     // general method split     void split()     {         // ... actual code here (not empty)     } }; 

Need to specialise this in the Triangle class case.. something like

template <> struct Node <Triangle*> {     // specialise the split method     void split() {} } ; 

but I don't want to rewrite the entire template over again! The only thing that needs to change is the split() method, nothing more.

Answer 1

You can provide a specialization for only that function outside the class declaration.

template <typename T> struct Node {     // general method split     void split()     {         // implementation here or somewhere else in header     } }; 

// prototype of function declared in cpp void splitIntNode( Node & node );

template <> void Node<int>::split() {      splitIntNode( this ); // which can be implemented }  int main(int argc, char* argv[]) {    Node <char> x;    x.split(); //will call original method    Node <int> k;    k.split(); //will call the method for the int version } 

If splitIntNode needs access to private members, you can just pass those members into the function rather than the whole Node.