Re: [tutoriald-design] Design Goals

[<reh...@t-...>]

On 11 Aug 2003, Leandro Guimarães Faria Corsetti Dutra wrote:

> Em Seg, 2003-08-11 às 06:32, Brian Olsen escreveu:
> > In thinking about creating an implementation of Tutorial D, we should
> > figure out what the design goals are, given the time, knowledge and
> > other factors involved.
> >
> > - I think it makes sense, and it seems to be the consensus, to
> > implement over Duro. The process of creating the language is then
> > simplified to a degree.
>
> 	Agreed.  Actually, one can consider the language is already created, if
> we want *Tutorial* D.

Yes, there is already a LALR(1) grammar available at the third manifesto
website.

I would prefer implementing Tutorial D; it's a language which is both
small and powerful, and I think it is the purest embodiment of the
D concepts (As it apprears to me, purer than D4, which has cursors,
as opposed to Tutorial D). When designing Duro, I tried to be as close
to Tutorial D as possible.

In fact I was already planning to implement a Tutorial D interpreter
at some later time.

I want to implement a Tcl interface to Duro for one the next versions,
and this interface is supposed to contain an interpreter for
relational expressions, to make using the relational algebra easier.
My idea was to extend this interpreter step by step to a
Tutorial D interpreter.

By the way, if the project is not implementing Tutorial D, it should
not be named Tutorial D.

So my idea would be to implement an interpreter for Tutorial D
as defined in the TTM. I agree with Leandro that we should start with
the data access parts. OK, Tutorial D is not industrial strength,
which means it lacks some features required for a 'real' language.

But these are mainly two: I/O operations and error handling.
It should be not very difficult to add I/O operations, and
for the first version(s) the error handling could just be having the
interpreter exit with an error message. Later some TRY ... CATCH
construct could be added to the language.

--
Rene'