June 2018 Update

Task/Read-a-configuration-file/Common-Lisp/read-a-configuration-file-1.lisp

@@ -1,10 +1,40 @@
-;config-file.txt
-;lisp comments works normally as it would in lisp
-#S(config-file
-:fullname "Foo Barber"
-:favoritefruit "banana"
-:needspeeling t
-:seedsremoved nil
-:otherfamily '("Rhu Barber" "Harry Barber")
-;:will "not be read"
-)
+(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))

Task/Read-a-configuration-file/Common-Lisp/read-a-configuration-file-2.lisp

@@ -1,9 +1,12 @@
-;config-file.lisp
-(defstruct config-file :fullname :favoritefruit :needspeeling :seedsremoved :otherfamily)
-(with-open-file (in "config-file.txt")
-  (defvar contents (read in))
-  (format t "~a~%" contents)
-  ;reading the config-file into a structure gives us
-  ;some helper functions to access individualy each element
-  (format t "Fullname: ~a~%" (config-file-fullname contents))
-  (format t "Contents is a config-file? ~a~%" (config-file-p contents)))
+READ-CONFIG> (with-open-file (s "test.cfg") (parse-config s))
+#<HASH-TABLE :TEST EQUAL :COUNT 4 {100BD25B43}>
+READ-CONFIG> (maphash (lambda (k v) (print (list k v))) *)
+
+("FULLNAME" "Foo Barber")
+("FAVOURITEFRUIT" "banana")
+("NEEDSPEELING" T)
+("OTHERFAMILY" ("Rhu Barber" "Harry Barber"))
+NIL
+READ-CONFIG> (gethash "SEEDSREMOVED" **)
+NIL
+NIL