Tim Attwood <tim### [at] anti-spamcomcastnet> wrote:
> // misformed #declare
> #declare Weird = #declare Aval = 1;

> // other properly formed statements
> #declare PigVal = pigment {rgb <0,0,0>};
> #declare ObjVal = sphere {<0,0,0>,1};

> #if (true=true)
> #local c=0;
> #while (c=0)

> // this object ends the misformed #declare and doesn't render
> object {pass_text}

> // this object renders normally
> object {fail_text}

> #local c=1;
> #end
> #end 

  As I said, the way the parser works is not always completely intuitive.

  Your example is a perfect example. It makes perfect sense when you know
how the parsing of #declares works, even if this kind of parsing sometimes
results in odd behavior like in your example.

  What is happening is that when the parser sees the very first "#declare",
it then parses an identifier name and a '='. After this it calls recursively
itself, asking itself for something which can be assigned to an identifier.
The very first thing which pops up is that first "object" block. Thus that
gets assigned to the first identifier.

  Of course since the parser is calling itself recursively, if there are
any other #-commands in-between, those will get parsed as their own entities,
before the parser gets to that first "object" block.

  As said, the behavior is not buggy per se, but a side-effect of the
recursive nature of the parser. Sometimes these side-effects produce
unintuitive results.

-- 
                                                          - Warp

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