Re: Using environment for OO

["Martin C. Martin" <martin@...>]

You and Eike are right.  In my application, the classes I'm dealing with 
only have a single object, so I mixed the fields in with the class.  Of 
course, if I wanted to apply this to any class with more than a single 
object, this won't work.  I'm surprised I didn't catch that myself -- 
guess my kids have been waking me up too early, too many days in a row 
or something.  :)

Thanks,
Martin

David Given wrote:
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> Martin C. Martin wrote:
> [...]
> > My "new" function takes a table to use for the object, so it goes
> > through it an calls setfenv() on each function[...]
>
> But, assuming I've understood what you're talking about correctly, this
> way you'll have to have a *different* function for every instance of the
> object. So x.foo and y.foo cannot refer to the same function foo(), even
> if x and y are instances of the same class.
>
> [...]
> > function MyClass.new(obj)
>
> If I do:
>
> o = { foo = function foo() end }
> x = MyClass.new(o)
> y = MyClass.new(o)
>
> ...then when x is created, o.foo's environment will be updated to point
> to x; then when y is created, o.foo's environment will be updated to
> point to y. Since x.foo == y.foo == o.foo, calling x.foo() will call the
> method with y as the environment. I assume this isn't what you want?
>
> (I could be misunderstanding what you mean here; I haven't used function
> environments much beyond sandboxing.)
>
> - --
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