Structured data

.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/structured_data.clj

@@ -1,16 +1,18 @@
 (ns structured-data)
 
 (defn do-a-thing [x]
-  :-)
+  (let [twice-x (+ x x)]
+    (Math/pow twice-x twice-x)))
 
 (defn spiff [v]
-  :-)
+  (+ (get v 0) (get v 2)))
 
 (defn cutify [v]
-  :-)
+  (conj v "<3"))
 
 (defn spiff-destructuring [v]
-  :-)
+  (let [[x _ y] v]
+    (+ x y)))
 
 (defn point [x y]
   [x y])
@@ -19,96 +21,115 @@
   [bottom-left top-right])
 
 (defn width [rectangle]
-  :-)
+  (let [[[x1 y1] [x2 y2]] rectangle]
+    (- x2 x1)))
 
 (defn height [rectangle]
-  :-)
+  (let [[[x1 y1] [x2 y2]] rectangle]
+    (- y2 y1)))
 
 (defn square? [rectangle]
-  :-)
+  (= (width rectangle) (height rectangle)))
 
 (defn area [rectangle]
-  :-)
+  (* (width rectangle) (height rectangle)))
 
 (defn contains-point? [rectangle point]
-  :-)
+  (let [[[x1 y1] [x2 y2]] rectangle
+        [x y] point]
+    (and (<= x1 x x2) (<= y1 y y2))))
 
 (defn contains-rectangle? [outer inner]
-  :-)
+  (let [[p1 p2] inner]
+    (and (contains-point? outer p1) (contains-point? outer p2))))
 
 (defn title-length [book]
-  :-)
+  (count (:title book)))
 
 (defn author-count [book]
-  :-)
+  (count (:authors book)))
 
 (defn multiple-authors? [book]
-  :-)
+  (> (author-count book) 1))
 
 (defn add-author [book new-author]
-  :-)
+  (assoc book :authors
+    (conj (:authors book) new-author)))
 
 (defn alive? [author]
-  :-)
+  (not (contains? author :death-year)))
 
 (defn element-lengths [collection]
-  :-)
+  (map count collection))
 
 (defn second-elements [collection]
-  :-)
+  (let [get-second (fn [v] (get v 1))]
+    (map get-second collection)))
 
 (defn titles [books]
-  :-)
+  (map :title books))
 
 (defn monotonic? [a-seq]
-  :-)
+  (or (apply <= a-seq)
+      (apply >= a-seq)))
 
 (defn stars [n]
-  :-)
+  (apply str (repeat n "*")))
 
 (defn toggle [a-set elem]
-  :-)
+  (if (contains? a-set elem)
+    (disj a-set elem)
+    (conj a-set elem)))
 
 (defn contains-duplicates? [a-seq]
-  :-)
+  (> (count a-seq) (count (set a-seq))))
 
 (defn old-book->new-book [book]
-  :-)
+  (assoc book :authors
+    (set (:authors book))))
 
 (defn has-author? [book author]
-  :-)
+  (contains? (:authors book) author))
 
 (defn authors [books]
-  :-)
+  (apply clojure.set/union (map :authors books)))
 
 (defn all-author-names [books]
-  :-)
+  (set (map :name (authors books))))
 
 (defn author->string [author]
-  :-)
+  (let [{name :name
+         birth-year :birth-year
+         death-year :death-year} author]
+    (str name
+         (if birth-year
+           (str " (" birth-year " - " death-year ")")))))
 
 (defn authors->string [authors]
-  :-)
+  (apply str (interpose ", " (map author->string authors))))
 
 (defn book->string [book]
-  :-)
+  (str (:title book) ", written by " (authors->string (:authors book))))
 
 (defn books->string [books]
-  :-)
+  (if (empty? books)
+    (str "No books.")
+    (str (count books) " book" (if (> (count books) 1) "s") ". "
+         (apply str (interpose ". " (map book->string books))) ".")))
 
 (defn books-by-author [author books]
-  :-)
+  (filter (fn [book] (has-author? book author)) books))
 
 (defn author-by-name [name authors]
-  :-)
+  (first (filter (fn [author] (= name (:name author))) authors)))
 
 (defn living-authors [authors]
-  :-)
+  (filter alive? authors))
 
 (defn has-a-living-author? [book]
-  :-)
+  (boolean (seq (living-authors (:authors book)))))
 
 (defn books-by-living-authors [books]
-  :-)
+  (filter has-a-living-author? books))
 
 ; %________%