> > There is a third path that one might consider, if it makes sense (in
> > particular, the package needs to have some kind of persistent state, 
or
> > able to get at some from the Rexx implementation), and that is: let 
the
> > user choose.
> >
> > APL (I think it was) does this: essentially when starting to write a
> > program using the package, you set a flag (to 0 or 1, perhaps) saying
> > whether to use 0-based or 1-based indexing, according to preference. 
 The
> > package then adjusts all indexes as requested.
> >
> > You still have to decide what the default should be (unless not 
specifying
> > is an error), but that's a much easier (read: less stressful) decision 
if
> > there's a way to override it.   (I'd agree with Chip on what the 
default
> > should be :-).)
> 
> When I started reading this thread, APL's "index origin" came
> immediately to mind. But in this case I find a REXX "astonishment
> factor" -- not in its behaviour, but in that its author would agree
> with and even propose something I imagined would be shot down in
> moments. Instead, everyone seems to like it!
> 
> APL started with a global index origin, settable only as an overall
> and external attribute of a workspace, and not capable of being set or
> interrogated by the running program. This soon changed, but I believe
> in most implementations it was/is still a global value not related to
> any concept of package, or at least not to any package smaller than
> the entire workspace.

That's the difference in what I was proposing ... the changeable index 
would be relate to and affect only to the particular package (for which 
the documentation, we are told, uses 0-indexing).  Definitely not a global 
setting, and definitely not changing Rexx's inherent indexing (in, for 
example, the built-in functions such as POS or WORD). 

I agree the latter would be disasterous ...

Mike 








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