Predicate exercises

.travis.yml

@@ -1,6 +1,6 @@
 language: clojure
-lein: lein2
-script: lein2 midje :config .midje-grading-config.clj
+lein: lein
+script: lein midje :config .midje-grading-config.clj
 jdk:
   - openjdk7
 notifications:

src/predicates.clj

@@ -1,41 +1,41 @@
 (ns predicates)
 
 (defn sum-f [f g x]
-  :-)
+  (+ (f x) (g x)))
 
 (defn less-than [n]
-  :-)
+  (fn [k] (< k n)))
 
 (defn equal-to [n]
-  :-)
+  (fn [k] (== k n)))
 
-(defn set->predicate [a-set]
-  :-)
+(defn set->predicate [a-set] (fn [x] (if (contains? a-set x) true false)))
 
-(defn pred-and [pred1 pred2]
-  :-)
+(defn pred-and [pred1 pred2] (fn [x] (and (pred1 x) (pred2 x))))
 
-(defn pred-or [pred1 pred2]
-  :-)
+(defn pred-or [pred1 pred2] (fn [x] (or (pred1 x) (pred2 x))))
 
 (defn whitespace? [character]
   (Character/isWhitespace character))
 
-(defn blank? [string]
-  :-)
+(defn blank? [string] (every? whitespace? string))
 
-(defn has-award? [book award]
-  :-)
+(defn has-award? [book award] (contains? (:awards book) award))
 
-(defn HAS-ALL-THE-AWARDS? [book awards]
-  :-)
+(defn HAS-ALL-THE-AWARDS? [book awards] (every? (fn [x] (has-award? book x)) awards))
 
 (defn my-some [pred a-seq]
-  :-)
+  (let [filtered-map (filter (fn [x] (boolean x)) (map pred a-seq))]
+    (if (< 0 (count filtered-map))
+      (first filtered-map)
+      false)))
 
 (defn my-every? [pred a-seq]
-  :-)
+  (let [filtered-map (filter (fn [x] (boolean x)) (map pred a-seq))]
+    (if (== (count filtered-map) (count a-seq)) true false)))
 
 (defn prime? [n]
-  :-)
+  (let
+    [pred (fn [x] (== (rem n x) 0))]
+    (not (some pred (range 2 n)))))
 ;^^