Support object does'n have < method

mrbgems/mruby-enum-ext/mrblib/enum.rb

@@ -58,9 +58,8 @@ module Enumerable
 
   def take(n)
     raise TypeError, "no implicit conversion of #{n.class} into Integer" unless n.respond_to?(:to_int)
-    raise ArgumentError, "attempt to take negative size" if n < 0
-
-    n = n.to_int
+    i = n.to_int
+    raise ArgumentError, "attempt to take negative size" if i < 0
     ary = []
     self.each do |*val|
       break if ary.size >= n