diff options
Diffstat (limited to 'gnu/services/configuration.scm')
-rw-r--r-- | gnu/services/configuration.scm | 29 |
1 files changed, 21 insertions, 8 deletions
diff --git a/gnu/services/configuration.scm b/gnu/services/configuration.scm index 2ad3a637a4..0a2219e743 100644 --- a/gnu/services/configuration.scm +++ b/gnu/services/configuration.scm @@ -1,5 +1,6 @@ ;;; GNU Guix --- Functional package management for GNU ;;; Copyright © 2015 Andy Wingo <wingo@igalia.com> +;;; Copyright © 2017 Mathieu Othacehe <m.othacehe@gmail.com> ;;; ;;; This file is part of GNU Guix. ;;; @@ -36,6 +37,7 @@ configuration-field-default-value-thunk configuration-field-documentation serialize-configuration + define-maybe define-configuration validate-configuration generate-documentation @@ -85,16 +87,27 @@ (configuration-field-name field) val)))) fields)) +(define-syntax-rule (id ctx parts ...) + "Assemble PARTS into a raw (unhygienic) identifier." + (datum->syntax ctx (symbol-append (syntax->datum parts) ...))) + +(define-syntax define-maybe + (lambda (x) + (syntax-case x () + ((_ stem) + (with-syntax + ((stem? (id #'stem #'stem #'?)) + (maybe-stem? (id #'stem #'maybe- #'stem #'?)) + (serialize-stem (id #'stem #'serialize- #'stem)) + (serialize-maybe-stem (id #'stem #'serialize-maybe- #'stem))) + #'(begin + (define (maybe-stem? val) + (or (eq? val 'disabled) (stem? val))) + (define (serialize-maybe-stem field-name val) + (when (stem? val) (serialize-stem field-name val))))))))) + (define-syntax define-configuration (lambda (stx) - (define (id ctx part . parts) - (let ((part (syntax->datum part))) - (datum->syntax - ctx - (match parts - (() part) - (parts (symbol-append part - (syntax->datum (apply id ctx parts)))))))) (syntax-case stx () ((_ stem (field (field-type def) doc) ...) (with-syntax (((field-getter ...) |