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Re: implementation of SRFI 96 for Larceny

This page is part of the web mail archives of SRFI 96 from before July 7th, 2015. The new archives for SRFI 96 contain all messages, not just those from before July 7th, 2015.

Will Clinger has successfully ported SRFI-96 and SLIB to Larceny.
Some of his comments in
are relevant to SRFI-96.

 | ; FIXME:  This should really be ".sch", but then SLIB wouldn't work.
 | (define (scheme-file-suffix) ".scm")

scheme-file-suffix would have been more appropriately named
slib-source-file-suffix.  It is specific to SLIB files.

 | ;;; FIXME:
 | ;;; SLIB appears to need these things, even though SRFI 96 doesn't
 | ;;; specify them or indicate that implementations of SRFI 96 must
 | ;;; define them.
 | (define (macro:eval . args) (apply slib:eval args))
 | (define (macro:load . args) (apply load args))

That was true of the first version of SRFI-96, and has been rectified.

 | ;;; FIXME:  With Larceny's implementation of defmacro,
 | ;;; macros that have been defined using defmacro are
 | ;;; indistinguishable from macros that have been defined
 | ;;; using Larceny's low-level explicit-renaming facility.
 | ;;;
 | ;;; For SLIB, however, it's probably good enough to pretend
 | ;;; that all low-level macros were defined using defmacro.
 | ;;;
 | ;;; FIXME:  This is terribly representation-dependent,
 | ;;; and will break when (not if) the representation of
 | ;;; macros changes.
 | (define (defmacro? m)
 |   (let ((x (environment-get-macro (interaction-environment) m)))
 |     (and x (procedure? (cadr x)))))

I will remove defmacro? from SRFI-96.

 | ;;; FIXME:  The specification of defmacro:eval says it
 | ;;; has to use slib:eval, but the definition of
 | ;;; defmacro:load says no such thing.
 | (define defmacro:load load)

I will change the wording for defmacro:eval to mirror slib:eval
instead of referring to it.

  Function: defmacro:eval e
    Returns the value of evaluating scheme expression e where all its
    defmacros have been expanded.

 | ;;; FIXME:  There doesn't seem to be any analogue of
 | ;;; macroexpand-1 in Larceny.
 | (define (macroexpand-1 e) (macro-expand e))

macroexpand-1 is a Common-Lisp legacy which I think was useful for
debugging defmacros, but which doesn't need to be supported.  I will
remove it from SRFI-96.

I have added an explanation of the relationship between macroexpand
and defmacro:expand*.

I have uploaded the updated srfi-96.html to: