Re: Build language with weak typing, then add scaffolding later to strengthen it?

["Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>]

On Sat, 30 May 2015 03:28:51 -0700 (PDT), jan.de.kruyf@gmail.com wrote:

> For the old man a language is "right" when the EBNF diagram is "right" or perhaps "beautiful".

BNF describes the language syntax or a formal language. Formal language <<<
programming language. Since 60's there is nothing interesting you could
describe in BNF or in any other syntactic formalism. We do know how "good"
syntax looks like.

> All his life Wirth has striven to get that part right,

You mean IF-THEN-ELSE, did he? (:-))

BTW, in all Wirth books I ever read he used directed graphs for syntax
definitions instead of BNF.

> So if you want to do any cleaning up I would say lets start with drawing
> up a EBNF of Ada.

ARM Annex P.

That is less than 0.1% of what constitutes a programming language.

> It will explain the critique from Dijkstra and Wirth,

It wasn't for Ada syntax AFAIK.

> And the biggest bonus will be that we will be able to work faster, once we
> have a good understanding of the mathematical underpinnings of the
> language.

Which ones? There is no problem parsing Ada. It is trivial, in fact. There
is little or nothing to understand there from a mathematical point of view. 

And this is not a problem people have with Ada. Even those, who dearly want
curly brackets and = for assignment, should understand that grammatically
there would be absolutely NO difference. Whether the end token is "end" or
"}" matters only aesthetically.

Few syntax problems Ada has come straight from Wirth himself. E.g.
different syntax for declarations of subprogram types and values (bodies)
from other types and values. Wirth seems never cared much about types.

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de