Question

The three initialize methods of this class are very, very, very similar. I’d like to see if there’s a way to chain the calls together, potentially into the method that requires both arguments. Thanks.

AudioHandler.h

class AudioHandler {

public:
    static bool Initialize(const SoundLibrary& sl);
    static bool Initialize(const Soundtrack& st);
    static bool Initialize(const SoundLibrary& sl, const Soundtrack& st);
    static void Release();
private:
    static const SoundLibrary* _sl;
    static const Soundtrack* _st;
};

AudioHandler.cpp

bool AudioHandler::Initialize(const SoundLibrary& sl) {
    if(_sl != NULL || _st != NULL) return false;

    unsigned long numVoices = 0;

    //If allegro is unable to initialize the sound drivers then return false.
    if((numVoices = detect_digi_driver(DIGI_AUTODETECT)) == 0) return false;
    if(install_sound(DIGI_AUTODETECT, MIDI_NONE, NULL) == -1) return false;
    _sl = &sl;

    return true;
}

bool AudioHandler::Initialize(const Soundtrack& st) {
    if(_sl != NULL || _st != NULL) return false;

    if(detect_midi_driver(MIDI_AUTODETECT) == 0) return false;
    if(install_sound(DIGI_NONE, MIDI_AUTODETECT, NULL) == -1) return false;
    _st = &st;

    return true;
}

bool AudioHandler::Initialize(const SoundLibrary& sl, const Soundtrack& st) {
    if(_sl != NULL || _st != NULL) return false;

    unsigned long numVoices = 0;

    if((numVoices = detect_digi_driver(DIGI_AUTODETECT)) == 0) return false;
    if(detect_midi_driver(MIDI_AUTODETECT) == 0) return false;
    if(install_sound(DIGI_AUTODETECT, MIDI_AUTODETECT, NULL) == -1) return false;

    _sl = &sl;
    _st = &st;

    return true;
}

void AudioHandler::Release() {
    _sl = NULL;
    _st = NULL;
    remove_sound();
}

Answer 1

1. Leave 3rd variant only.
2. Change references to pointers.
3. Send NULL for the arguments you don’t need.
4. Check for NULL before doing specific code.

PS: in your current version, storing the address of a passed reference in the object is not a good idea.