updated to work with the new laziness

improvements to syntax highlighting
rebuilt dependencies
other minor edits

Author: stuarthalloway

README

@@ -15,13 +15,13 @@ DEPENDENCIES
 
 This version of the sample code has been tested with:
 
-Clojure SVN revision 1279
-svn co -r 1279 http://clojure.googlecode.com/svn/trunk/ clojure    
+Clojure SVN revision 1299
+svn co -r 1299 http://clojure.googlecode.com/svn/trunk/ clojure    
 
-Clojure-Contrib SVN revision 459:
-svn co -r 459 http://clojure-contrib.googlecode.com/svn/trunk/ clojure-contrib     
+Clojure-Contrib SVN revision 505:
+svn co -r 505 http://clojure-contrib.googlecode.com/svn/trunk/ clojure-contrib     
 
-Compojure GIT commit 0c8eff9
+Compojure GIT commit 0fa49377
 
 -------------------------------------------------------------------------------
 You can run the completed Compojure example with

examples/functional.clj

@@ -54,12 +54,15 @@
      :else (fib [0 1] 2)))) 
 ; END: fibo-series
 
-; START: lazy-cons-fibo
-(defn lazy-cons-fibo []
-  ((fn fib [a b] ; <label id="code.lazy-cons.fib"/>
-     (lazy-cons a (fib b (+ a b)))) ; <label id="code.lazy-cons.recur"/>
-   0 1)) ; <label id="code.lazy-cons.basis"/>
-; END: lazy-cons-fibo
+; START: lazy-seq-fibo
+(defn lazy-seq-fibo 
+  ([] 
+     (concat [0 1] (lazy-seq-fibo 0 1)))
+  ([a b]
+     (let [n (+ a b)]
+       (lazy-seq
+	(cons n (lazy-seq-fibo b n))))))
+; END: lazy-seq-fibo
 
 ; START: head-fibo
 ; holds the head (avoid!)
@@ -80,9 +83,11 @@
 
 ; START: by-pairs
 (defn by-pairs [coll]
-  (let [pair (take 2 coll)] ; <label id="code.by-pairs.take"/>
-    (when (= 2 (count pair)) ; <label id="code.by-pairs.count"/>
-      (lazy-cons pair (by-pairs (rest coll)))))) ; <label id="code.by-pairs.lazy"/>
+  (let [take-pair (fn take-pair [c]
+		    (when (next c) (take 2 c)))]
+    (lazy-seq
+     (when-let [pair (seq (take-pair coll))]
+	 (cons pair (by-pairs (rest coll)))))))
 ; END: by-pairs
 
 ; START: count-heads-by-pairs

examples/lazy_index_of_any.clj

@@ -1,9 +1,10 @@
 (ns examples.lazy-index-of-any)
 
-(defn logging-seq [s]
-  (if s
-    (do (println "Iterating over" (first s))
-	(lazy-cons (first s) (logging-seq (rest s))))))
+(defn logging-seq [coll]
+  (lazy-seq
+   (when-let [s (seq coll)]
+       (do (println "Iterating over" (first s))
+	   (cons (first s) (logging-seq (rest s)))))))
 
 (defn indexed [s] (map vector (iterate inc 0) s (logging-seq s)))
 (defn index-filter [pred coll]

examples/replace_symbol.clj

@@ -6,10 +6,10 @@
 (defmulti replace-symbol coll-or-scalar) ; <label id="code.replace-symbol.multi"/>
 
 (defmethod replace-symbol :collection [coll oldsym newsym]
-  (if (empty? coll)
-    coll
-    (lazy-cons (replace-symbol (first coll) oldsym newsym) ; <label id="code.replace-symbol.lazy-cons"/>
-	       (replace-symbol (rest coll) oldsym newsym))))
+  (lazy-seq
+   (when-let [s (seq coll)]
+    (cons (replace-symbol (first coll) oldsym newsym) ; <label id="code.replace-symbol.lazy-cons"/>
+	  (replace-symbol (rest coll) oldsym newsym)))))
 
 (defmethod replace-symbol :scalar [obj oldsym newsym] 
   (if (= obj oldsym) newsym obj))

examples/test/functional.clj

@@ -19,8 +19,8 @@
 (deftest test-fibo-series
   (is (= ten-fibs (fibo-series 10))))
 
-(deftest test-lazy-cons-fibo
-  (is (= ten-fibs (take 10 (lazy-cons-fibo)))))
+(deftest test-lazy-seq-fibo
+  (is (= ten-fibs (take 10 (lazy-seq-fibo)))))
 
 (deftest test-head-fibo 
   (is (= ten-fibs (take 10 head-fibo))))

lib/clojure-contrib.jar

@@ -5,10 +5,10 @@ public static boolean isBlank(String str) {
       return true; 
     }  
     for (int i = 0; i < strLen; i++) { 
-	if ((Character.isWhitespace(str.charAt(i)) == false)) { 
-	    return false; 
-	}
+	    if ((Character.isWhitespace(str.charAt(i)) == false)) { 
+	      return false; 
+	    }
     }
     return true;
   }
-}
+}