:: Re: [DNG] OT: Algol w, 68, Pascal, …
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Autore: Didier Kryn
Data:  
To: dng
Oggetto: Re: [DNG] OT: Algol w, 68, Pascal, Ada
Le 04/07/2016 19:25, Hendrik Boom a écrit :
> On Mon, Jul 04, 2016 at 06:32:38AM +0200, Didier Kryn wrote:
>> Le 03/07/2016 23:17, Hendrik Boom a écrit :
>>> On Fri, Jun 24, 2016 at 01:36:14PM -0400, Peter Olson wrote:
>>>
>>>> Can I download your compiler that fixes all my mistakes? I could really use such a tool.
>>> Yes, as a matter of fat you can -- almost.
>>>
>>> Two languages I use have the property that once the program gets
>>> through the compiler, almost all the bugs are gone.
>>>
>>> Modula 3.
>>> OCaml.
>>>
>>> Algol 68 is another one, but Algol 68 compilers are as scarce as hen's
>>> teeth nowdays.
>>>
>>>
>>      Ada also. BTW, Ada is considered a descendant of Pascal, which is a
>> descendant of Algol68 :-)
> More a relative.  Wirth made a proposal for a language, van Wijngaarden
> made a proposal for a defining formalism.  Algol 68 was the result of
> merging the language ideas with the formalism, generalising wherever
> that worked, and imposing orthogonal design principles to simplify
> everytthing conceptually.

>
> Wirth was sufficienly upset with the result that he implemented a
> variant of his original design, quickly, acoiding whatever was tricky
> to implement, and called it Algol W. He made all caracter strings
> fixed-length (which ws diffeent from his original proposal. Later
> he made Pascal. I'd call Pascal a descendant of Algol W rather than of
> Algol 68. Pascal had an easier syntax to parse, simpler parameter
> passing conventions, and required array sizes to be statically
> determined,
>
> It ignored most of the new ideas introduced by Algol 68.
>
>>      Ada is generally used when human life is at stake - planes, rockets, air
>> traffic control, automatic vehicles.
> Ada resembled Pascal syntactically, but had very different semantics.
> For one thing, it was type-safe.  Pascal wasn't.  I'm not sure
> I'd really call it a descendant.

>
>

     Cheers Hendrik. You know this history much better than me.


     So let's say these languages share a few typical features: 
instructions go across lines and they terminate with ';' (introduced by 
Algol60 I think), they use ':=' for the assignment instruction, they use 
the same words to denote basic types (Boolean, Integer, Natural), and 
they're wordy.


     Didier