Re: [stack] disallowing recursive definitions

On Mar 3, 2008, at 19:16 , John Nowak wrote:

>
> On Mar 3, 2008, at 3:50 PM, William Tanksley, Jr wrote:
>
>>> With a concatenative tail-call you're passing the stack as an
>>> argument. In other words, you pass the entire state of the program!
>>
>> Yes, this is how concatenative languages are modeled. That's how
>> *every* step in their execution is modeled, not just tail-calls or
>> calls. If this were a problem, concatenative languages would be
>> universally problematic, not merely problematic in the presence of
>> tail-calls.
>
> Indeed, and I'd argue that this is exactly why many people find stack-
> based languages universally problematic. They're taking issue with all
> of this state passing, although they phrase it like "I can't keep the
> stack in my head". Of course this isn't a problem in practice,
> particularly when you have type inference involved and can get a quick
> summary of what a function cares about, but it does seem to be the
> source of many negative first impressions.

Also, there has never been a requirement to "keep it all in one's head,"
that's what comments are for. Commenting with stack diagrams is very
useful!

I know "real programmers" don't comment but in these languages, they
should.
--
don



> - John
>
>
>
> Yahoo! Groups Links
>
>
>
>