From: Martin DeMello <martindemello@...>
Date: 2002-11-29T21:16:35+09:00
Subject: Re: RCR: Stack, Queue alias methods in Array

Kent Dahl <kentda@stud.ntnu.no> wrote:
> Martin DeMello wrote:
> 
> If you're still not convinced, there's a little something that stuck to
> my mind all day:
> 
> Push, pop and peek,
> on their own were rather meek.
> But their combined whack,
> made quite a stack,
> with an interface that sounds quite sleek.

There is really no reason to stop
With defining a 'push' and a 'pop'
But a function called 'peek'
Isn't all that unique
I would much rather see it called 'top'

And a plausible use of 'peek' paired with 'shift' rather than 'pop'
would be looking at the first argument to a function without shifting
that argument out.

>> 'expose the internal data structure' 
>> and probably a
>> couple of other things (remember BASIC's 'peek'?)
> 
> Yes, I remember. But how many come to Ruby from a Basic that uses peek
> these days? :-P

Can you even *get* a Basic that uses peek these days? I think C is the
last bastion of pointer arithmetic :)
 
>> Cafeterias, for example, use push-down stacks of plates. The plates sit
>> in a vertical cage, with a spring at the bottom, so that the top plate
>> is always at the same height. You literally push in a plate - the others
>> get pushed downwards and teh spring compresses, and likewise you can
>> only remove the top plate.
> 
> Can't argue with that. Or can I? A more frequented stack-like structure
> encountered IRL by programmers, I would assume to be the coffee machine
> and (somewhat) the water cooler. Usually, in my experience, they have a
> stack of cups where you remove at the bottom, from a cylindrical plastic
> encasing, to avoid the cup being full of dust. :-)

But don't you put in new cups from the top? Which would make it a queue
rather than a stack.

martin