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Potential change in sample implementation - comments?

This page is part of the web mail archives of SRFI 110 from before July 7th, 2015. The new archives for SRFI 110 contain all messages, not just those from before July 7th, 2015.

I'm thinking about adding and using a macro in the
to simplify the Scheme reference implementation.
Any comments?

Currently, the sample implementation includes
many lines that look like this:
; Run (n-expr-first port) and put results in various variables
(let* ((basic-full-results (n-expr-first port))
       (basic-special      (car basic-full-results))
       (basic-value        (cadr basic-full-results)))

I'm thinking about using an R5RS-style macro
so all such lines would instead look like:
(let-splitter (basic-full-results basic-special basic-value)
  (n-expr-first port)

The macro definition would look like this:
; I'm intentionally requiring exactly 3 variables for now, since
; that's all that's used.  It could be modified later to be more flexible.
(define-syntax let-splitter
  (syntax-rules ()
    ((let-splitter (full first-value second-value) expr body ...)
      (let* ((full expr)
             (first-value (car full))
             (second-value (cadr full)))
             body ... ))))

Guile 1.8 doesn't enable R5RS macros by default, but they can be enabled with:
  (use-syntax (ice-9 syncase))
It appears that the same is true for guile 1.6:
I believe most other Schemes in wide use have R5RS macros.
Even old/partial Schemes that did NOT support R5RS macros
should be easily adaptable (it doesn't particularly require a hygenic macro system).
I'd probably do the same with the Common Lisp implementation
(that's outside this group's scope, but I thought I'd mention it).

Comments?  Good idea? Bad idea?

--- David A. Wheeler