"Mr" <m******r******at_hotmail_dot_fr> wrote:
>I'm not referring to type here which is another issue, just the
> "declare" or "var" keyword... I don't see why it's important.

A "big" difference is that in POV-Ray you have to tell a variable whether it is
local or not. In many languages this is different. Every variable declared
inside a block is local and it can't escape that block.

So in Nim:

var chicken = 1

for i in 0 ..< 10:
  let n = i + i
  chicken += n

echo chicken
echo n # fails compilation, Error: undeclared identifier: 'n'

it fails not because it is let (immutable), but because it's local.

There is quite a body of research on what a good beginners language should look
like. Python scores very high on these. One aspect in several of these
researches made me chuckle, as I had the same problem decades ago. It is hard to
grasp 'while' and 'for' loops (Warp wrote a tutorial on it). Using the keyword
'every 'makes it more understandable for novices. Another hard one is OOP except
for the composition of records/objects.

The main problem in POV-Ray is that there are two aspects to it, the 'scripting'
part and the 'objects' part and that is actually well done. Compare it with the
javascript 3D stuff, or Vapory https://github.com/Zulko/vapory . If one would
repurpose an existing language for POV-Ray SDL then look for a language with
extensive macro abilities to build a DSL so one can have a distinct render
object sections an distinct script/code sections, similar to POV-Ray now.

ingo

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