Prev: Slime with Squeeze?
Next: Anybody mind to translate this Felleisen quote from German to English
From: joswig on 24 Feb 2010 13:55
On 24 Feb., 19:47, piscesboy <oraclmas...(a)gmail.com> wrote:
> On Feb 24, 1:24 pm, Tamas K Papp <tkp...(a)gmail.com> wrote:
>
> > On Wed, 24 Feb 2010 06:50:48 -0800, piscesboy wrote:
> > > number of slots available to a class is supposed to be implementation
> > > dependent
>
> > This is probably my ignorance, but where does it say this in the HS?
>
> > Thanks,
>
> > Tamas
>
> Hmmmm...I wondered about that too, so I read it again, here:
>
> http://cl-cookbook.sourceforge.net/clos-tutorial/index.html
>
> Section 3. Classes and Instances:
>
> "Structures can have any number of slots, from zero up (to some
> implementation-defined limit, e.g. 254 in LispWorks for Windows) and -
> as with lists and general vectors - the slots can hold any values."
>
> but I don't know whether it applies to classes in CLOS per se, even
> though they are technically structures.
>
> But anyway, this may be a superfluous detail that doesn't help me
> solve a problem as to why a class I created cannot even handle 8 slots
> let alone 254.

How about posting your code, so that we can see what it wrong?
From: Ron Garret on 24 Feb 2010 14:30
In article
<f26609e2-e61d-483b-8aab-375e754eedef(a)b2g2000yqi.googlegroups.com>,
piscesboy <oraclmaster(a)gmail.com> wrote:

> On Feb 24, 11:38 am, p...(a)informatimago.com (Pascal J. Bourguignon)
> wrote:
> > piscesboy <oraclmas...(a)gmail.com> writes:
> > > Strangely, when I created a class instance in CLOS containing more
> > > than 8 slots, any slot values entered after the 8th are ignored. The
> > > number of slots available to a class is supposed to be implementation
> > > dependent, so how do I find out/change what it is for clisp on Mac OS
> > > X?
> >
> > I don't observe any problem:
> >
> > C/USER[19]> (defmacro defclass-with-a-lot-of-slots (class super
> > number-of-slots)
> >              `(defclass ,class ,super
> >                 ,(loop
> >                     for i from 0 below number-of-slots
> >                     for s = (intern (format nil "SLOT-~D" i))
> >                     for k = (intern (format nil "SLOT-~D" i) "KEYWORD")
> >                     collect `(,s :accessor ,s :initarg ,k))))
> > DEFCLASS-WITH-A-LOT-OF-SLOTS
> > C/USER[20]> (defclass-with-a-lot-of-slots a () 1000)
> > WARNING: DEFCLASS: Class A (or one of its ancestors) is being redefined,
> > instances are obsolete
> > #1=#<STANDARD-CLASS A :VERSION 1>
> > C/USER[21]> (defvar *a* (make-instance 'a :slot-999 999 :slot-60 60))
> > *A*
> > C/USER[22]> (defparameter *a* (make-instance 'a :slot-999 999 :slot-60 60))
> > *A*
> > C/USER[23]> (slot-60 *a*)
> > 60
> > C/USER[24]> (slot-999 *a*)
> > 999
> > C/USER[25]>
> >
> > --
> > __Pascal Bourguignon__
>
> I used the 'make-instance macro. Is that the issue?

I think the issue is that you're being dense. There is no such thing as
"the MAKE-INSTANCE macro." MAKE-INSTANCE is a generic function.

Whatever problem you are having, it isn't what you think. Post a
transcript.

rg
From: Captain Obvious on 24 Feb 2010 14:00
p> Strangely, when I created a class instance in CLOS containing more
p> than 8 slots, any slot values entered after the 8th are ignored. The
p> number of slots available to a class is supposed to be implementation
p> dependent, so how do I find out/change what it is for clisp on Mac OS
p> X?

8 slots per class would be just ridiculous limitation.
So, either you have a bug in your code or CL implementation you're using is
broken.

From: Tim Bradshaw on 24 Feb 2010 17:35
On 2010-02-24 18:24:01 +0000, Tamas K Papp said:

> This is probably my ignorance, but where does it say this in the HS?

I can't find a limit specified (or even that there might be a limit)
either for instances of STANDARD-CLASS or STRUCTURE-CLASS. I may not
be looking carefully enough though, and it is probably implicitly no
more than ARRAY-TOTAL-SIZE-LIMIT.

It's clear the OP has some confusion I think.

First  |  Prev  | 
Pages: 1 2
Prev: Slime with Squeeze?
Next: Anybody mind to translate this Felleisen quote from German to English