[Haskell] Dynamic binding

[Andreas Rossberg]

Ralf Lammel wrote:
> 
>>"dynamic binding" is just the OOO way of saying
>>"calling a first-class function").
> 
> Let me presume that dynamic binding 
> was meant here in the sense of late binding

Yes.

> in the sense of subtyping polymorphism.

No, as far as I read it, "dynamic" or "late binding" is orthogonal to 
subtyping, or typing in general. It is just that most typed OO languages 
lump these concepts together.

For me, "dynamic" or "late" binding just means calling (or more 
generally, accessing) something that is not determined statically. That 
is precisely what first-class functions provide.

Objects just turn more complex uses of this idiom into a language 
concept. Operationally, objects are equivalent to records of first-class 
functions. They usually come with more flexible typing and more 
efficient implementation, though.

> (First-class function seems to refer to currying or what?)

No, constructing closures, and passing them around as values (currying 
is merely a particularly convenient special case of this).

> (Did you miss a "polymorphic" before function? That would explain it.

I don't understand what you mean. Polymorphism is about typing. Late 
binding is not dependent on typing (there are untyped OO languages, for 
example).

Cheers,

   - Andreas

[Followups to Haskell Cafe]

-- 
Andreas Rossberg, rossberg at ps.uni-sb.de

Let's get rid of those possible thingies!  -- TB