OpenEuphoria

RE: Eu's design

• Posted by kbochert at copper.net Aug 18, 2003
• 378 views

On 18 Aug 2003 at 7:57, Matt Lewis wrote:

> > > It seems that what you'd like to do is store the stack 
> > > itself outside of the stack code's source file, and
> > > pass it by reference.  You could still do somehting 
> > > like this, albeit without the pass by reference (think
> > > append/prepend).  It wouldn't be very elegant, but that's 
> > > what you get for forcing a design.
> >
> > Forcing a design? What's wrong with doing it efficiently?
> > Please read the last posts.
> 
> I don't see what efficiency is really gained by storing 
> the data locally and passing by reference versus storing
> the data where it will be manipulated and passing an 
> index.  Either way, you're passing a 'pointer' of sorts.
> You've just decided that one 'pointer' is good, and 
> another is bad, and I don't understand the reasons
> behind the judgment.
> 
The issue is a combination of efficiency and modularization.
If a function is intended to operate on a single instance of a
sequence, then indexes work fine.  If a function is designed
to work sometimes on one sequence, and sometimes on
another, then the sequence being operated on is a
'variability' of the function, and should be passed in as 
an argument.  Think of a library function that is intended
to transform a sequence containing XML for instance.
Because it doesn't know ahead of time what sequence it must
operate on, it must be passed the sequence.  A small change
to the XML can result in a huge amount of copying,
referencing and dereferencing without some way of PBR'ing.


Karl Bochert