Re: [stack] What does "concatenative" actually mean?

John Nowak scripsit:

> In a concatenative language, one thing you can do as add the 'world'  
> to the top of the stack and have all operations work below it except  
> those that perform IO. This does let you sort of hand-wave and claim  
> the language is purely functional. The problem is that *everything*  
> now has a forced evaluation order, not just those things that perform  
> IO. In other words, even though your language is purely functional,  
> you're still essentially stuck with having to use eager evaluation.  
> This is why I claim this approach is mostly hand-waving; it doesn't  
> let you do anything different than you otherwise would.

Nobody ever claimed that Joy was lazy; "pure functional" does not mean
"pure, functional, and lazy".  Lazy languages have their virtues, but
so do eager ones.

Similarly, it has a type system, just not a static type system.  Those too
have their disadvantages: I find it useful that languages like Scheme
and Joy can have fully heterogeneous lists.

-- 
May the hair on your toes never fall out!       John Cowan
        --Thorin Oakenshield (to Bilbo)         [email protected]