undefined method get with sinatra

I have following code

require 'rubygems'
require 'sinatra'

get '/' do
  'Hello World!'
end


gem list sinatra

*** LOCAL GEMS ***

sinatra (1.0, 0.9.4)


ruby -v
ruby 1.8.7 (2009-06-12 patchlevel 174) [i68开发者_如何学JAVA6-darwin10.2.0]

Error

 ruby myapp.rb 
["==", "===", "=~", "__id__", "__send__", "class", "clone", "display", "dup", "enum_for", "eql?", "equal?", "extend", "freeze", "frozen?", "hash", "id", "include", "inspect", "instance_eval", "instance_exec", "instance_of?", "instance_variable_defined?", "instance_variable_get", "instance_variable_set", "instance_variables", "is_a?", "kind_of?", "method", "methods", "nil?", "object_id", "private", "private_methods", "protected_methods", "public", "public_methods", "respond_to?", "send", "singleton_methods", "taguri", "taguri=", "taint", "tainted?", "tap", "to_a", "to_enum", "to_s", "to_yaml", "to_yaml_properties", "to_yaml_style", "type", "untaint"]
./sinatra.rb:17: undefined method `get' for main:Object (NoMethodError)
    from /usr/local/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in `gem_original_require'
    from /usr/local/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in `require'
    from myapp.rb:3

Is it possible that you have file named "sinatra.rb" in the same folder as the file you're running? "Require" checks the local directory first, so if there's one there, it won't go find the real gem.

[1] https://sinatra.lighthouseapp.com/projects/9779/tickets/295-sinatra-hello-world-error