Files
sex/utils.scm
alex-eg 878e0ad210 modularize sex
Also rename macros to sex-macros, module-system to sex-modules for
clarity, uniformity, and to avoid name clashes with Chicken's
units/modules named "macros" and "modules"
2026-04-29 21:55:38 +03:00

67 lines
1.6 KiB
Scheme

(import
scheme
(chicken base)
(chicken pathname)
(chicken process-context)
srfi-1)
(define-syntax prog1
(syntax-rules ()
((prog1 form . forms)
(let ((res form))
(begin . forms)
res))))
(define-syntax with-directory
(syntax-rules ()
((with-directory path form . forms)
(let ((current-dir (current-directory)))
(set-working-directory path)
(prog1
(begin form . forms)
(change-directory current-dir))))))
(define (get-env-var name)
(get-environment-variable name))
(define (set-working-directory file)
(change-directory
(normalize-pathname
(if (absolute-pathname? file)
(pathname-directory file)
(make-absolute-pathname
(current-directory)
(pathname-directory file))))))
(define (to-absolute-pathname pathname)
(if (absolute-pathname? pathname)
pathname
(make-absolute-pathname
(current-directory)
pathname)))
(define (list-split src-list split-elt)
;; split '(1 2 / 3 4 / 5 6) by '/ -> '((1 2) (3 4) (5 6))
(fold (lambda (elt acc)
(if (eq? elt split-elt)
(append acc (list (list)))
(append (drop-right acc 1)
(list (append (last acc) (list elt))))))
(list (list))
src-list))
(define (list-join lists join-by)
(drop-right
(fold (lambda (elt acc)
(append acc (list elt) (list join-by)))
(list)
lists)
1))
;;; Reconstruct form
(define (recons old-cons new-car new-cdr)
(if (and (eq? new-car (car old-cons))
(eq? new-cdr (cdr old-cons)))
old-cons
(cons new-car new-cdr)))