error handling

parking.scm

@@ -7,6 +7,7 @@
 (import (chicken io))
 (import srfi-13)
 (import srfi-14)
+(import (chicken condition))
 
 (define (curry fn a)
   (lambda (b)
@@ -73,7 +74,9 @@
 
 ;;; Get data from a uri and parse it as json.
 (define (simple-json-request uri)
-  (with-input-from-request uri #f read-json))
+  (condition-case (with-input-from-request uri #f read-json)
+    ((exn i/o net) (begin (display-newline "Connection failed.")
+                          (exit 1)))))
 
 ;;; The API key is an alphanumeric string of length 32
 ;;; The Linköping municipal open data API key generator portal is located at http://opendata.linkoping.se