From: Eric Mahurin <eric_mahurin@...>
Date: 2005-05-07T01:29:05+09:00
Subject: Re: object reference handle (like perl's reference to scalar)

Nope.  You need a dereferencing operator/method just like C. 
Otherwise you'd be assigning to the reference itself rather
than what it points to.  Here would be the equivalents to C:

C     Ruby/ref
----  --------
p=&a  p=ref{:a}
*p    p[]
*p=   p[]=

You can reference/dereference just about anything with this
ruby scheme instead of just a place in memory like you do in C.

Actually, thinking about it more, I'm going to pull this
reference API into another project I'm working on: "cursor".  A
Cursor is what some also call an "external iterator" (see
Iterator on rubyforge), but mine is going to be more general. 
With this class, you'll be able to do this type of thing to
correlate even more to the C pointer:

C                Ruby
---------------  -----
int a[]={0,1,2}  a=[0,1,2]  # a is already a pointer in C
int *p = a       p = Cursor::Indexable(a)
*p               p[]
*p=              p[]=
*(++p)           p.succ![]
*(++p)=          p.succ![]=

So, a Cursor is a Reference that you can move around in a data
structure (anything sequential - even an IO).  Just like you
can move a pointer around in a data structure to
reference/dereference different elements.

I haven't made and uploaded a "reference" gem yet (or
"cursor").  All I've done is reserved the name on rubyforge. 
Feel free to play around with what I previously posted and
comment.

p.s. my middle initial is W and I'm 6'2"

> is it possible to remove the [] appendix? :-)
> 
> something like,
> 
> hacker = ["bot","pen","a",5,10]
> 
> name  = hacker.ref[0..2]
> fname = name.ref[0]
> lname = name.ref[1]
> mname = name.ref[2]
> 
> height = hacker.ref[3..4]
> feet   = height.ref[1]
> inches = height.ref[2]
> 
> fname = "Eric"
> lname = "Mahurin"
> mname = "?"
> 
> feet   = 6
> inches = 5
> 
> name    #=> ["Eric","Mahurin","?"]
> height  #=> [6,5]
> hacker  #=> ["Eric","Mahurin","?",6,5]
> 
> 
> Possible?
> 
> btw, i cannot download your reference gem...
> 
> thanks and kind regards -botp



		
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