RosettaCodeData/Task/Read-a-configuration-file/Common-Lisp/read-a-configuration-file-1.lisp
2018-06-22 20:57:24 +00:00

40 lines
1.2 KiB
Common Lisp

(ql:quickload :parser-combinators)
(defpackage :read-config
(:use :cl :parser-combinators))
(in-package :read-config)
(defun trim-space (string)
(string-trim '(#\space #\tab) string))
(defun any-but1? (except)
(named-seq? (<- res (many1? (except? (item) except)))
(coerce res 'string)))
(defun values? ()
(named-seq? (<- values (sepby? (any-but1? #\,) #\,))
(mapcar 'trim-space values)))
(defun key-values? ()
(named-seq? (<- key (word?))
(opt? (many? (whitespace?)))
(opt? #\=)
(<- values (values?))
(cons key (or (if (cdr values) values (car values)) t))))
(defun parse-line (line)
(setf line (trim-space line))
(if (or (string= line "") (member (char line 0) '(#\# #\;)))
:comment
(parse-string* (key-values?) line)))
(defun parse-config (stream)
(let ((hash (make-hash-table :test 'equal)))
(loop for line = (read-line stream nil nil)
while line
do (let ((parsed (parse-line line)))
(cond ((eq parsed :comment))
((eq parsed nil) (error "config parser error: ~a" line))
(t (setf (gethash (car parsed) hash) (cdr parsed))))))
hash))