added version increment script

.scripts/vincr.zp

@@ -0,0 +1,30 @@
+(define (die msg)
+  (begin
+    (write msg)
+    (exit 1)))
+
+(define (usage)
+  (die "increment_version [position]\n\tposition defaults to 2"))
+
+(define (parse-args)
+  (cond
+    ((eq? 0 (length zepto:args)) 2)
+    ((and (string:num? (car zepto:args))
+          (eq? 1 (length zepto:args)))
+      (string->number (car zepto:args)))
+    (else (usage))))
+
+(define (main position)
+  (if (not (file-exists? "VERSION"))
+    (die "A version file is needed in the current directory")
+    (let* ((version (read-contents "VERSION"))
+           (new-version (|> (string:split version ".")
+                            (curry map string->number)
+                            list->vector
+                            ($ (vector:update % position add1))
+                            (curry vector:map number->string)
+                            ($ (string:join % ".")))))
+      (with-output-file "VERSION" (curry write new-version)))))
+
+(main (parse-args))
+(exit 0)