Question

I’m working on a fairly complex project, a custom encryption routine if you will (just for fun) and I’ve run into this issue in designing my code layout.

I have a number of functions that I want to be able to call by index. Specifically, I need to be able to call one randomly for the encrypt process, but then address that by a specific index in the decrypt process.

I was considering a classic function array, but my main concern is that a function array would be tricky to maintain, and a little ugly. (The goal is to get each function pair in a separate file, to reduce compile times and make the code easier to manage.) Does anyone have a more elegant C++ solution as an alternative to a function array? Speed isn’t really an issue, I’m more worried about maintainability.

-Nicholas

Answer 1

You could write something like:

class EncryptionFunction { public:     virtual Foo Run(Bar input) = 0;     virtual ~MyFunction() {} };  class SomeSpecificEncryptionFunction : public EncryptionFunction {     // override the Run function };  // ...  std::vector<EncryptionFunction*> functions;  // ...  functions[2]->Run(data); 

You could use operator() instead of Run as the function name, if you prefer.