= Class =

''Part of'' TutorialFundamentals

== Description ==

A class is a similiar idea to a struct, but allows more abstract designs.

== Example ==

{{{
#!d
import std.stdio;

class Television { 

    void pressPowerButton() {
        if(m_turnedOn)
            writefln("It was on, but now you turned it off.");
        else
            writefln("Now, it's turned on (channel %d).", m_channel);
        m_turnedOn = !m_turnedOn;
    }

    void changeChannel(int c) {
        if(m_turnedOn) {
            if(c == m_channel) {
                writefln("It's already on channel %d, silly.", m_channel);
            }
            else { 
                m_channel = c;
                writefln("Per your request, it's now on channel %d.", m_channel);
            }
        }
        else {
            writefln("Hmm... the TV's off. Try turning it on before you pick a channel.", m_channel);
        }
    }

    this() {
        m_turnedOn = false;  
        m_channel = 3;
        writefln("\n(Creating this object is kind of like plugging in a TV set.)\n");
    }

    ~this() {
        writefln("\n(Destroying this object is kind of like unplugging a TV set.)\n");
    }

    private {
        bool m_turnedOn;
        int m_channel;
    }
}


void main() {     
    Television bigScreen = new Television;

    bigScreen.pressPowerButton();
    bigScreen.changeChannel(44);
    bigScreen.changeChannel(49);
    bigScreen.changeChannel(49);
    bigScreen.pressPowerButton();
    bigScreen.changeChannel(34);
    bigScreen.pressPowerButton();
    bigScreen.changeChannel(34);
    bigScreen.changeChannel(49);
    bigScreen.pressPowerButton();

    delete bigScreen;
}
}}}

== Source ==

Based on [http://jcc_7.tripod.com/d/tutor/simple/class.html class.html] by jcc7.