POV-Ray : Newsgroups : povray.beta-test : POV-Ray v3.8.0-alpha.9945627 : Re: POV-Ray v3.8.0-alpha.9945627 Server Time
20 Jun 2021 20:58:41 EDT (-0400)
  Re: POV-Ray v3.8.0-alpha.9945627  
From: jr
Date: 5 Dec 2018 11:25:02
Message: <web.5c07fb1cb0fe7d71e43b71790@news.povray.org>
hi,

clipka <ano### [at] anonymousorg> wrote:
> Am 05.12.2018 um 01:24 schrieb jr:
> > ... unintended?
> >
> No, that's entirely intentional. Commas are always optional, provided
> that this doesn't lead to ambiguity.

I have the feeling I knew but then forgot.  :-(


> This will declare a 3-dimensional vector. On the other hand, the
> following will declare a 2-dimensional vector:
>
>      #declare Foo = <1 -2 3>;
>
> That's because POV-Ray interprets `1 -2` as the expression `1-2`, i.e.
> the single value -1.

heh, a real trap for the unwary.


while on punctuation,  following your reply to ingo on brackets etc (facepalm
moment :-)) I re-read the declaring arrays section (3.3.1.10.1), and noticed in
the table titled "Additional usage examples are as follows" the use of
semicolons after the #undefs.  the documentation (3.3.2.2.4) offers no
explanation.

so when I added semicolons to my recent 'queues.inc' ([*]  I know it's not the
same since I'm not removing dictionary keys, just .. experimenting), I found
that of the four (near) identical uses, two throw an error while the other
two work unchanged.

the error is:  Parse Error: Expected 'numeric expression', ; found instead

occurring in the get/pop macros but working in the destroys.

the respective line numbers, referring to the file posted: 41 + 102 are ok, 57 +
115 cause "trouble".


regards, jr.

[*] http://news.povray.org/web.5be1d482cfca02966427f7f90%40news.povray.org


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