* lib/irb/ruby-lex.rb (RubyLex::getc): should not push nil into

reading buffer (@readed).  reported in
  <http://jarp.does.notwork.org/diary/200608c.html#200608311>.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@10815 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

sample/occur.rb

@@ -1,8 +1,8 @@
 # word occurrence listing
 # usege: ruby occur.rb file..
 freq = Hash.new(0)
-while gets()
-  for word in split(/\W+/)
+while line = gets()
+  for word in line.split(/\W+/)
     freq[word] += 1
   end
 end