From 07ffe68ad9145a209725ac289f8c4235b4c9b334 Mon Sep 17 00:00:00 2001
From: David Rajchenbach-Teller <dteller@mozilla.com>
Date: Thu, 3 Nov 2011 09:37:45 +0100
Subject: [PATCH] uint.rs: added functions div_ceil, div_floor, div_round

---
 src/lib/uint.rs          | 23 +++++++++++++++++++++++
 src/test/stdtest/uint.rs |  7 +++++++
 2 files changed, 30 insertions(+)

diff --git a/src/lib/uint.rs b/src/lib/uint.rs
index a9ea4d03c90..561acc66d66 100644
--- a/src/lib/uint.rs
+++ b/src/lib/uint.rs
@@ -34,6 +34,29 @@ pure fn mul(x: uint, y: uint) -> uint { ret x * y; }
 /* Function: div */
 pure fn div(x: uint, y: uint) -> uint { ret x / y; }
 
+/**
+ * Divide two numbers, return the result, rounded up.
+ */
+pure fn div_ceil(x: uint, y: uint) -> uint {
+    let div = div(x, y);
+    if x % y == 0u { ret div;}
+    else { ret div + 1u; }
+}
+
+/**
+ * Divide two numbers, return the result, rounded to the closest integer.
+ */
+pure fn div_round(x: uint, y: uint) -> uint {
+    let div = div(x, y);
+    if x % y * 2u  < y { ret div;}
+    else { ret div + 1u; }
+}
+
+/**
+ * Divide two numbers, return the result, rounded down.
+ */
+pure fn div_floor(x: uint, y: uint) -> uint { ret x / y; }
+
 /* Function: rem */
 pure fn rem(x: uint, y: uint) -> uint { ret x % y; }
 
diff --git a/src/test/stdtest/uint.rs b/src/test/stdtest/uint.rs
index 0ba2ac39c1d..28546f4a6f1 100644
--- a/src/test/stdtest/uint.rs
+++ b/src/test/stdtest/uint.rs
@@ -102,3 +102,10 @@ fn test_overflows() {
    assert (uint::min_value() <= 0u);
    assert (uint::min_value() + uint::max_value() + 1u == 0u);
 }
+
+#[test]
+fn test_div() {
+    assert(uint::div_floor(3u, 4u) == 0u);
+    assert(uint::div_ceil(3u, 4u)  == 1u);
+    assert(uint::div_round(3u, 4u) == 1u);
+}
\ No newline at end of file