Re: unexpected return value

[Stephen C. Gilardi]

On Jul 2, 2009, at 1:48 PM, Mark Volkmann wrote:

(defn match [prev-char next-char]
 (cond = prev-char
   \( (= next-char \))
   \[ (= next-char \])
   true false))

It looks like you intended condp here instead of cond.



----------
volkmann.clj (on classpath):
----------

(ns volkmann)

(defn match [prev-char next-char]
 (condp = prev-char
   \( (= next-char \))
   \[ (= next-char \])
   false))

(defn main
  []
  (prn
   (match \( \))
   (match \r \))))

----------
using clojure.contrib.repl-utils/run
----------

user=> (run volkmann)
true false
nil
user=>

--Steve

Your test works as expected if you make that change. However, there's another correction required to allow match to work in the general case. The last clause should be "false" instead of "true false". If it's not, then any prev-chars except \(, \[, and true will throw an exception.

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