From 55c1942b43b1e62956e6ce1798dc10fe742d617c Mon Sep 17 00:00:00 2001
From: "Yukihiro \"Matz\" Matsumoto" <matz@ruby-lang.org>
Date: Mon, 17 Mar 2014 00:04:34 +0900
Subject: add Enumerable#first to mruby-enum-ext

---
 mrbgems/mruby-enum-ext/mrblib/enum.rb | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/mrbgems/mruby-enum-ext/mrblib/enum.rb b/mrbgems/mruby-enum-ext/mrblib/enum.rb
index f250d39f1..85779ee59 100644
--- a/mrbgems/mruby-enum-ext/mrblib/enum.rb
+++ b/mrbgems/mruby-enum-ext/mrblib/enum.rb
@@ -161,4 +161,30 @@ module Enumerable
     h
   end
 
+  NONE = Object.new
+  ##
+  # call-seq:
+  #    enum.first       ->  obj or nil
+  #    enum.first(n)    ->  an_array
+  #
+  # Returns the first element, or the first +n+ elements, of the enumerable.
+  # If the enumerable is empty, the first form returns <code>nil</code>, and the
+  # second form returns an empty array.
+  def first(n=NONE)
+    if n == NONE
+      self.each do |e|
+        return e
+      end
+      return nil
+    else
+      a = []
+      i = 0
+      self.each do |e|
+        break if n<=i
+        a.push e
+        i += 1
+      end
+      a
+    end
+  end
 end
-- 
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