In article <402d339c@news.povray.org> , Florian Brucker <tor### [at] torfboldcom>
wrote:

> Is there a reason for this behaviour?

Well, a #declare is a parse time "macro" while a variable name in a function
is a render time definition.  Hence, the substitution of the "A" has to
happen prior to the parser evaluating any expression.

This is also why it is not easy to find in the documentation, because it of
course is not mentioned explicitly in the function description section (it
does not belong there at all), but in the description of directives.
However, even there the detailed differences between a "macro" and variable
are not really explained formally as they are a rather computer science
based topic that is very hard to simplify and requires a heavy CS background
to really comprehend.

    Thorsten

____________________________________________________
Thorsten Froehlich, Duisburg, Germany
e-mail: tho### [at] trfde

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