[plt-scheme] Re: Is R6RS useless for PLT?

From: Matthias Felleisen (matthias at ccs.neu.edu)
Date: Tue Nov 18 10:22:39 EST 2008

On Nov 18, 2008, at 10:09 AM, Marc Feeley wrote:

> The diversity of Scheme implementations should be viewed as one of  
> the strengths of Scheme, not a weakness.

Marc, we agree with this statement very much as far as the idea of  
Scheme is concerned. Because there are so many implementations  
around, I am hopeful that Scheme will survive me in some for or other  
and that no matter how it survives some of the ideas we developed for  
Scheme will survive in this form.

For a working programmer, though, Scheme is an idea -- a  
specification of a family of languages -- and for most working  
programmers, the contexts and constraints are pretty clear. So it  
usually suffices to pick a particular Scheme programming language,  
say Gambit or PLT, and to work with it. The porting programmers are few.

 From this perspective, an R6RS implementation serves as a bridge  
between distinct Scheme implementations. If you have chosen a  
specific language for its power (one of my scripts for submitting NSF  
proposals is 10 lines of code; in R5RS it's 120) and you do discover  
the need for a port, you first move from PLT to its R6RS  
specification -- in an interoperating manner -- and then you move it  
to Gambit's R6RS, possibly incorporating Gambit-specific features as  
you re-deploy your product.

We should not expect more from a 'common standard' and not less. --  

Posted on the users mailing list.