Re: [stack] Properties of Concatenative langauges and Forth

On Fri, Jan 2, 2009 at 10:20 PM, John Cowan <[email protected]> wrote:
> Christopher Diggins scripsit:
>
>> Talking about data-flow in the context of Joy is incorrect. A Joy
>> program has no data, only functions. You'll see what I mean below.
>
> Well, sort of. 5 is a number in Joy, even if it's a function too.
> As a function, it can be applied to the stack; but if it's on the stack,

As a syntactic phrase in the Joy language, the symbol "5" has one
meaning: it is a function that takes a stack as input and returns a
copy of the input stack, with a value "5" on top. Dually we can
explain it is an instruction that pushes a value "5" on a shared
stack. In either case the value "5" on a stack is distinct from the
instruction "5".

- Christopher