Re: [office-formula] General question (not yet a JIRA issue)

["Andreas J. Guelzow" <aguelzow@math.concordia.ab.ca>]

On Fri, 2009-12-11 at 13:28 -0500, Patrick Durusau wrote:
> Andreas,
> 
> Andreas J. Guelzow wrote:
> > On Fri, 2009-12-11 at 09:17 -0500, Patrick Durusau wrote:
> >   
> >> Greetings,
> >>
> >> When looking at TYPE I read:
> >>
> >>     
> >>> Portable documents *shall not* depend on receiving a value of 4.
> >>>
> >>>       
> >> Since TYPE returns a number indicating a value type, I am not real sure 
> >> what it means to "not depend on receiving a value of 4." ???
> >>
> >> BTW, 4 is logical.
> >>
> >> So a portable document could accept some other number for logical type? 
> >> Or doesn't recognize logical type? Or if it does, then it isn't a 
> >> portable document?
> >>
> >>     
> >
> > 4.4:
> > Logical values may be implemented as a distinct, distinguishable type
> > from numbers, so that ISNUMBER(TRUE()) and ISLOGICAL(1) evaluates to
> > FALSE(). However, logical values may also be implemented as a subtype of
> > Number, where TRUE() simply returns 1 and FALSE() simply returns 0. Note
> > that due to the implicit conversion operator “Number to
> > Logical” (discussed below), when a number is passed as a condition, 0 is
> > considered False and all other numeric values are considered True.
> >
> > So there may not be a Logical type. For example OOo does not implement a
> > LOGICAL type.
> >
> >   
> Well, but saying that a "portable" document doesn't accept some 
> particular value isn't the same thing as saying that a portable document 
> doesn't support Logical type.

But it does mean that a portable document cannot use the TYPE function
if the final return value of the expression may depend on whether the
evaluator has a distinct Logical type or not.

Andreas  


-- 
Andreas J. Guelzow, PhD, FTICA
Mathematical & Computing Sciences
Concordia University College of Alberta