[chuck-users] chuck-users Digest, Vol 17, Issue 11

[Scott Wheeler]

kijjasak triyanond wrote:
> Oh.. yes yes & yes!
> this is the OOP idea i'm not familiar with.
> so this is how it works.. wow.
> new item.. and new @ variable.. wow.
> i was always trying to do something like this with other stuffs.
> but i didn't use @ for a new pointer variable..
>
> i had no idea hahah.. thanks Scott. this is so clear.
> and it gives me a lot of new ideas & a breakthrough for more things i 
> can do in ChucK!

Actually, if it's being used for instructional purposes, I feel like I 
should post the cleaned up version:

class IntStack
{
    class Item
    {
        0 => int value;
        Item @ below;
    }

    Item bottom @=> Item top;

    fun void push(int value)
    {
        Item item;
        value => item.value;
        top @=> item.below;
        item @=> top;
    }

    fun int pop()
    {
        top.value => int value;

        if(!isEmpty())
        {
            top.below @=> top;
        }

        return value;
    }

    fun int isEmpty()
    {
        return top == bottom;
    }
}


This is one of the syntactic quirks of ChucK -- the following are 
equivalent:

Item foo;
new Item @=> Item @ foo;

...which I feel like is an unnecessary ambiguity.  The syntax roughly 
mimics C++ in both cases, but in C++ those would be quite different.


-Scott