Scala : cleanup, Scala : add sumCurry

1 files changed, 30 insertions, 0 deletions

diff --git a/Scala/sandbox/curry.scala b/Scala/sandbox/curry.scala
new file mode 100644
index 0000000..910de62
--- /dev/null
+++ b/Scala/sandbox/curry.scala
@@ -0,0 +1,30 @@
+
+object Curry {
+
+  // high order function
+  def sum(f: Int => Int, a: Int, b: Int) = {
+    def loop(a: Int, acc: Int): Int  =
+      if (a > b) acc
+      else loop(a + 1, f(a) + acc)
+    loop(a, 0)
+  }
+
+  // curry version: this function return an (Int, Int) => Int function
+  def sumCurry(f: Int => Int): (Int, Int) => Int = {
+    def sumF(a: Int, b: Int): Int  =
+      if (a > b) 0
+      else f(a) + sumF(a + 1, b)
+    sumF
+  }
+
+  def sumInts   = sumCurry(x => x)
+  def sumCubes  = sumCurry(x => x * x)
+
+  def run = {
+    println("Curry")
+    println(sum(x => x * x, 3, 5))
+    println(sumInts(3, 5))
+    println(sumCubes(3, 5))
+  }
+
+}