From d29e1d49116c66adab72b1c1bb49c1fa3d4f8140 Mon Sep 17 00:00:00 2001
From: Carlo Zancanaro <carlo@zancanaro.id.au>
Date: Sat, 30 May 2015 02:00:43 +1000
Subject: Initial commit: only works for plain int typed arguments

---
 src/main/java/au/id/zancanaro/Generators.java | 35 +++++++++++++++++++++++++++
 1 file changed, 35 insertions(+)
 create mode 100644 src/main/java/au/id/zancanaro/Generators.java

(limited to 'src/main/java/au/id/zancanaro/Generators.java')

diff --git a/src/main/java/au/id/zancanaro/Generators.java b/src/main/java/au/id/zancanaro/Generators.java
new file mode 100644
index 0000000..f065d1d
--- /dev/null
+++ b/src/main/java/au/id/zancanaro/Generators.java
@@ -0,0 +1,35 @@
+package au.id.zancanaro;
+
+import java.util.Iterator;
+
+public class Generators {
+    @SafeVarargs
+    public static <T> Generator<T[]> arrayGenerator(Generator<? extends T>... generators) {
+        return Generator.tuple((Generator<T>[]) generators);
+    }
+
+    public static Generator<Integer> integerGenerator() {
+        return (random, size) -> {
+            int value = random.nextInt(size);
+            return new RoseTree<>(value, intShrinkingIterable(value));
+        };
+    }
+
+    private static Iterable<RoseTree<Integer>> intShrinkingIterable(final int value) {
+        return () -> new Iterator<RoseTree<Integer>>() {
+            int curr = value;
+
+            @Override
+            public boolean hasNext() {
+                return curr > 0;
+            }
+
+            @Override
+            public RoseTree<Integer> next() {
+                int prevCurr = curr;
+                curr = curr / 2;
+                return new RoseTree<>(value - prevCurr, intShrinkingIterable(value - prevCurr));
+            }
+        };
+    }
+}
-- 
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