Delegates

A delegate is a type-safe function pointer.
Available in any .NET language.
A C# example is:
```
delegate int Massage(string s);
```

Suppose we also declare:

private static int StringLength(string pString)
{
    return pString.Length;
}

We can now write:
```
Massage tMassage = new Massage(StringLength);
```
The variable tMassage now contains a pointer to the StringLength method.

A method can be written in terms of a parameter that is a delegate:

private static void iProcess(Massage pMassage)
{
    string tString = Console.ReadLine();
    int tInt = pMassage(tString);
    Console.WriteLine(tInt);
}

This contains the call:
```
int tInt = pMassage(tString);
```
The function that is to be called can be supplied as an argument when iProcess is called:
```
iProcess(tMassage);
```

If a delegate's return type is void, a delegate variable can be assigned a value that represents (not just one method but) a list of methods to be called.