Re: [stack] function/object ambiguity + quotation alternative

On Feb 26, 2009, at 3:11 PM, Stevan Apter wrote:

>>> the evaluator would not abide naked functions on the stack; it  
>>> would apply repeatedly until that was not the case.
>>
>> Then you have a first order language. I don't really see what that
>>
>> buys you. Why not allow functions on the stack? It seems to me that
>> higher-order languages are only a positive thing. Joy and its ilk are
>> only interesting to me because they allow functions on the stack.
>
> i don't disagree.

You should disagree unless you're suggesting that '5 [dup]' evaluate  
to '5 5'. Are you? I wasn't under the impression that you meant to  
make that point. If you weren't suggesting that, the language would  
remain higher-order.

> so in cat, what's on the stack after evaluating [dup]first?

This is not possible in Cat because quotations are not manipulatable  
as such. This is necessary to preserve extensionality (e.g. '[1 2  
drop] == [1]') and to allow the language to be typed.

- John