Switch to port-based reading/parsing

vcarded.scm

@@ -54,14 +54,6 @@
   (irregex-extract "(\\\\;|[^;])*" key-or-value))
 
 
-(define (parse-vcard-element kv-pair)
-  (case (car kv-pair)
-    ('VERSION
-     (append (list (car kv-pair) (string->number (second kv-pair)))
-             (cddr kv-pair)))
-    (else kv-pair)))
-
-
 ;; Parse a line of a vcard file into an alist-friendly format:
 ;;    (KEY ("keyprop1=d" "keyprop2=b") "VALUE" ("valprop1=a" "valprop2=b"))
 (define (parse-vcard-line line)
@@ -74,6 +66,25 @@
           (cdr value-elements))))
 
 
-(define (vcard-string->alist string)
+;; Reader thunk. Read/parse an entire vcard into a “vcard alist.”
-  (map parse-vcard-line (lines string)))
+(define (read-vcard)
+  (let [(element (read-vcard-element))]
+    (if (not (eof-object? (peek-char)))
+        (append (list element) (read-vcard))
+        element)))
 
+
+;; Read a single unfolded line into a vcard “element” list.
+(define (read-vcard-element)
+  (parse-vcard-line (read-folded-line)))
+
+
+;; Reader-thunk. Read a “logical” folded-line, where a line beginning with a
+;; space is a continuation of the previous line — like with vcards.
+(define (read-folded-line)
+  (let [(line (read-line))]
+    (if (eq? (peek-char) #\space)
+        (string-concatenate
+         (list line
+               (string-drop (read-element) 1)))
+        line)))