guile-prescheme/prescheme/bcomp/transform4.scm
2022-08-31 23:47:54 +10:00

33 lines
1 KiB
Scheme

;;; Ported from Scheme 48 1.9. See file COPYING for notices and license.
;;;
;;; Port Author: Andrew Whatson
;;;
;;; Original Authors: Mike Sperber
;;;
;;; scheme48-1.9.2/scheme/rts/low-syntax.scm
;;;
;;; Low-level support for different kinds of syntax transformers
;;;
;;; We just use a vector with a tag in slot 0. (Can't be a pair,
;;; because syntax transformers may be pairs of transformer and aux
;;; names.)
;;;
;;; 4-argument version of explicit-renaming transformers
;;; (expression name? rename compare)
(define-module (prescheme bcomp transform4)
#:export (make-explicit-renaming-transformer/4
explicit-renaming-transformer/4?
explicit-renaming-transformer/4-proc))
(define (make-explicit-renaming-transformer/4 proc)
(vector 'explicit-renaming-transformer/4 proc))
(define (explicit-renaming-transformer/4? thing)
(and (vector? thing)
(= 2 (vector-length thing))
(eq? 'explicit-renaming-transformer/4 (vector-ref thing 0))))
(define (explicit-renaming-transformer/4-proc thing)
(vector-ref thing 1))