[cells-devel] Re: [cello-devel] Constructor syntax

Thomas F. Burdick tfb at OCF.Berkeley.EDU
Mon May 10 23:35:35 UTC 2004


Kenny Tilton writes:

 > Thomas F. Burdick wrote:
 >
 > >Okay, how are these for a start?
 > >
 > >  (defmacro cv (&optional (value +unbound+))
 > >    `(cells::make-c-variable :value ,value))
 > >  
 > >  (defmacro c-formula ((&rest keys &key lazy cyclic-p cyclic-value) &body forms)
 > >    (declare (ignore lazy cyclic-p cyclic-value))
 > >    `(cells::make-c-dependent :code ',forms :rule (c-lambda , at forms)
 > >                              , at keys))
 > >  
 > >  (defmacro c-variable ((&rest keys &key cyclic-p) &optional (value nil valuep))
 > >    (declare (ignore cyclic-p))
 > >    `(cells::make-c-variable :value ,(if valuep value '+unbound+) , at keys))
 > 
 > looks ok. but...
 > 
 > 1. Is there a definition for +unbound+ missing?
 > 
 > 2. Maybe if I stare at it long enough it will come to me, but why not do 
 > on c-variable what is proposed for cv, viz.,:
 > 
 >       &optional (value '+unbound+)

Hmm, maybe I should have edited these on their way out of my utils
file.  +unbound+ is from (defconstant +unbound+ '+unbound+), from my
unbound-cells hack from before.  As for (2), yeah, that would be
simpler.  It was a mental-cut-and-paste error, from having written a
bunch of macros right before that, that needed the supplied-p value.




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