* NEWS: add Array#max, #min, and the optimization. [Feature #12172]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@54154 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

2 files changed, 19 insertions, 1 deletions

diff --git a/ChangeLog b/ChangeLog
index 916042c960..3eb9ae16b8 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,8 +1,12 @@
+Thu Mar 17 21:47:57 2016  Yusuke Endoh  <mame@ruby-lang.org>
+
+	* NEWS: add Array#max, #min, and the optimization.  [Feature #12172]
+
 Thu Mar 17 21:45:02 2016  Yusuke Endoh  <mame@ruby-lang.org>
 
 	* compile.c (NODE_CALL): add optimization shortcut for Array#max/min.
 	  Now `[x, y].max` is optimized so that a temporal array object is not
-	  created in some condition.
+	  created in some condition.  [Feature #12172]
 
 	* insns.def (opt_newarray_max, opt_newarray_min): added.
 
diff --git a/NEWS b/NEWS
index db4480aa45..0f08b3daf2 100644
--- a/NEWS
+++ b/NEWS
@@ -16,6 +16,12 @@ with all sufficient information, see the ChangeLog file or Redmine
 
 === Core classes updates (outstanding ones only)
 
+* Array
+  * Array#max and Array#min.  [Feature #12172]
+    This may cause a tiny incompatibility: if you redefine
+    Enumerable#max and call max to an Array, your redefinition will be
+    now ignored.  You should also redefine Array#max.
+
 * Dir
 
   * Dir.empty?.  [Feature #10121]
@@ -53,3 +59,11 @@ with all sufficient information, see the ChangeLog file or Redmine
 === Supported platform changes
 
 === Implementation improvements
+
+* In some condition, `[x, y].max` and `[x, y].min` are optimized
+  so that a temporal array is not created.  The concrete condition is
+  an implementation detail: currently, the array literal must have no
+  splat, must have at least one expression but literal, the length must
+  be <= 0x100, and Array#max and min must not be redefined.  It will work
+  in most casual and real-life use case where it is written with intent
+  to `Math.max(x, y)`.