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Re: isn't computation-rules redundant?

This page is part of the web mail archives of SRFI 53 from before July 7th, 2015. The new archives for SRFI 53 contain all messages, not just those from before July 7th, 2015.

On Fri, 26 Mar 2004, Andre van Tonder wrote:

> One rationale for the current decoupling of the defining form from the
> transformer (as in syntax-rules) is that
> one has a uniform way of denoting a transformer, whether it is bound to a
> name using define-syntax, bound using let(rec)-syntax, or used
> anonymously.  Your proposal, while more brief, conflates declaring the
> transformer and binding it, and only in define forms but not
> let(rec)-forms - in the latter you still have to write it out the long
> way.  
> I have another idea: instead of using define-syntax, introduce a
> form DEFINE-TRANSFORMER which will handle both syntax-rules and
> syntax-computations, and which can be portable extended to handle other
> kinds of tranformers should the need arise in future.  So one would write
>    (define-transformer name
>      (syntax-rules (...)  ...))
>    (define-transformer name
>      (syntax-computations (...) ...))
>    (define-transformer name
>      (lambda (stx) (syntax-case stx (...)  ...)
> and so on.  The same goes for LET-TRANSFORMER and LETREC-TRANSFORMER.

Huh?  This is the what DEFINE-SYNTAX _already_is_!  I don't care if a
couple implementations hardwire SYNTAX-RULES into DEFINE-SYNTAX; that
can easily be fixed, just as easily as introducing a new definition
form for macros.  What you propose here is _exactly_ what I _already_
suggested, except that I used the existing DEFINE-SYNTAX.