rlm@10: ;;  Copyright (c) Stephen C. Gilardi. All rights reserved.  The use and
rlm@10: ;;  distribution terms for this software are covered by the Eclipse Public
rlm@10: ;;  License 1.0 (http://opensource.org/licenses/eclipse-1.0.php) which can
rlm@10: ;;  be found in the file epl-v10.html at the root of this distribution.  By
rlm@10: ;;  using this software in any fashion, you are agreeing to be bound by the
rlm@10: ;;  terms of this license.  You must not remove this notice, or any other,
rlm@10: ;;  from this software.
rlm@10: ;;
rlm@10: ;;  clojure.contrib.condition.example.clj
rlm@10: ;;
rlm@10: ;;  scgilardi (gmail)
rlm@10: ;;  Created 09 June 2009
rlm@10: 
rlm@10: (ns clojure.contrib.condition.example
rlm@10:   (:use (clojure.contrib
rlm@10:          [condition
rlm@10:           :only (handler-case print-stack-trace raise *condition*)])))
rlm@10: 
rlm@10: (defn func [x y]
rlm@10:   "Raises an exception if x is negative"
rlm@10:   (when (neg? x)
rlm@10:     (raise :type :illegal-argument :arg 'x :value x))
rlm@10:   (+ x y))
rlm@10: 
rlm@10: (defn main
rlm@10:   []
rlm@10:   
rlm@10:   ;; simple handler
rlm@10:   
rlm@10:   (handler-case :type
rlm@10:     (println (func 3 4))
rlm@10:     (println (func -5 10))
rlm@10:     (handle :illegal-argument
rlm@10:             (print-stack-trace *condition*))
rlm@10:     (println 3))
rlm@10: 
rlm@10:   ;; multiple handlers
rlm@10:   
rlm@10:   (handler-case :type
rlm@10:     (println (func 4 1))
rlm@10:     (println (func -3 22))
rlm@10:     (handle :overflow
rlm@10:       (print-stack-trace *condition*))
rlm@10:     (handle :illegal-argument
rlm@10:       (print-stack-trace *condition*)))
rlm@10: 
rlm@10:   ;; nested handlers
rlm@10: 
rlm@10:   (handler-case :type
rlm@10:     (handler-case :type
rlm@10:       nil
rlm@10:       nil
rlm@10:       (println 1)
rlm@10:       (println 2)
rlm@10:       (println 3)
rlm@10:       (println (func 8 2))
rlm@10:       (println (func -6 17))
rlm@10:       ;; no handler for :illegal-argument
rlm@10:       (handle :overflow
rlm@10:         (println "nested")
rlm@10:         (print-stack-trace *condition*)))
rlm@10:     (println (func 3 4))
rlm@10:     (println (func -5 10))
rlm@10:     (handle :illegal-argument
rlm@10:       (println "outer")
rlm@10:       (print-stack-trace *condition*))))