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[Axiomdeveloper] Re: 1: %
From: 
Gabriel Dos Reis 
Subject: 
[Axiomdeveloper] Re: 1: % 
Date: 
22 Feb 2006 17:48:46 +0100 
Ralf Hemmecke <address@hidden> writes:
 Dear Gaby,

 On 02/22/2006 04:00 PM, Gabriel Dos Reis wrote:
 > Ralf Hemmecke <address@hidden> writes:
 >  On 02/22/2006 12:21 AM, Gabriel Dos Reis wrote:
 >  > Ralf Hemmecke <address@hidden> writes:
 >  >  >  The problem is the "1: %" as a constant (not a nullary
 >  > function).
 >  >  > The distinction is largely syntactic, not fundamental.
 >  >   I was once told that in Aldor the difference between
 >  >  a: %
 >  >  and
 >  >  b: () > %
 >  >  is that
 >  >  b() will run a program which might sideeffect other things or even
 >  >  return something different each time.
 >  > expanding on my preivous answer, have a look at the section 5.2 os
 >  > the
 >  > Aldor user guide on literal forming  you can define your own function
 >  > to interpret a string literal as a constant.
 >   I knew about this Literal stuff before...
 > I have no doubt about that :)
 > 
 > http://lists.gnu.org/archive/html/axiomdeveloper/200602/msg00154.html
 >   But as you see, if you write a domain that has a function
 >  string: Literal > %,
 >  it is a function and that means that "1" and "1" need not give
 >  identical values.
 > yes, that is precisely why I said in an earlier message that the
 > distinction is largely syntactic. it is not something fundamental in
 > the context of your discussion about axiom and o stuff.
 > Underneath, everything is a function in Aldor!

 Well, it might depend on which level you look at it. If the generated
 C code is concerned, I have no idea about that.
if we were to consider implementation details, then descending to the
foam level would suffice :)
However, I was really thinking of the abstract model  no
implementation involved yet.
 But if it were really just syntactic, then the output given below is
 strange.

 However, this behaviour is exactly, the difference between a constant
 and a nullary function in Aldor.
The difference is not that between a constant and a nullary function
 btw, anything defined with "==" is a constant in Aldor :)
if your nullary function y evaluates to the *same* value for same
argument each time, then it would do just fine. You won't see any
difference. The real difference in your program is that of *binding
time*.
 Aldor computes the value for x at the time the domain is
 instantiated. So it is constant over the lifetime of the domain
 (unless some dirty tricks change that value). For y it is
 different. That is a function constant. But a constant of type ()>%
 not of type %. Now, of course, if you say "y()", you get something of
 type %. But each time you call y() you might get a differen element of
 %.

 I guess, you know all this stuff.
yes, thanks. I'm still puzzled as to why you're collapsing binding time
distinction with constant vs. nullary function.
 gaby
 RE: [Axiomdeveloper] about Expression Integer, (continued)
 RE: [Axiomdeveloper] about Expression Integer, Bill Page, 2006/02/20
 Re: [Axiomdeveloper] about Expression Integer, Gabriel Dos Reis, 2006/02/20
 Re: [Axiomdeveloper] about Expression Integer, Ralf Hemmecke, 2006/02/21
 Re: [Axiomdeveloper] about Expression Integer, Gabriel Dos Reis, 2006/02/21
 [Axiomdeveloper] 1: %, Ralf Hemmecke, 2006/02/21
 [Axiomdeveloper] Re: 1: %, Gabriel Dos Reis, 2006/02/21
 [Axiomdeveloper] Re: 1: %, Gabriel Dos Reis, 2006/02/21
 [Axiomdeveloper] Re: 1: %, Ralf Hemmecke, 2006/02/22
 [Axiomdeveloper] Re: 1: %, Gabriel Dos Reis, 2006/02/23
 [Axiomdeveloper] Re: 1: %, Ralf Hemmecke, 2006/02/22
 [Axiomdeveloper] Re: 1: %,
Gabriel Dos Reis <=
 [Axiomdeveloper] Re: 1: %, Ralf Hemmecke, 2006/02/22
 Re: [Axiomdeveloper] about Expression Integer, Ralf Hemmecke, 2006/02/21
 Re: [Axiomdeveloper] about Expression Integer, Gabriel Dos Reis, 2006/02/20
 Re: [Axiomdeveloper] about Expression Integer, Ralf Hemmecke, 2006/02/21
 Re: [Axiomdeveloper] about Expression Integer, Gabriel Dos Reis, 2006/02/21
 RE: [Axiomdeveloper] about Expression Integer, Bill Page, 2006/02/20
 Re: [Axiomdeveloper] about Expression Integer, Ralf Hemmecke, 2006/02/21
 Re: [Axiomdeveloper] about Expression Integer, Ralf Hemmecke, 2006/02/21
 RE: [Axiomdeveloper] about Expression Integer, Bill Page, 2006/02/21
 Re: [Axiomdeveloper] about Expression Integer, Ralf Hemmecke, 2006/02/21