要求范围/宝石超出范围?

时间:2012-12-31 02:37:35

标签: ruby gem twitter

好吧,我在加载一个或多个特定库时遇到了一些问题,即该库可能超出了范围。这是在这种情况下发生的事情吗?

主要问题:需要函数中的库,以便它们可以在全局范围内使用。 例如:

   class Foo
      def bar
         require 'twitter_oauth'
         #....
      end
      def bar_2
         TwitterOAuth::Client.new(
            :consumer_key => 'asdasdasd',
            :consumer_secret => 'sadasdasdasdasd'
            )
      end
    end 

   temp = Foo.new
   temp.bar_2

现在解决我的问题我试图运行eval将它绑定到全局范围......就像这样

    $Global_Binding = binding
   class Foo
      def bar
         eval "require 'twitter_oauth'", $Global_Binding
         #....
      end
      def bar_2
         TwitterOAuth::Client.new(
            :consumer_key => 'asdasdasd',
            :consumer_secret => 'sadasdasdasdasd'
            )
      end
    end 

   temp = Foo.new
   temp.bar_2

但这似乎没有诀窍......任何想法?有没有更好的方法呢?

1 个答案:

答案 0 :(得分:1)

:一种。
文件test_top_level.rb:

puts '    (in TestTopLevel ...)'
class TestTopLevel
end

使用RSpec测试文件ttl.rb:

# This test ensures that an included module is always processed at the top level,
# even if the include statement is deep inside a nesting of classes/modules.

describe 'require inside nested classes/modules' do
#        =======================================

    it 'is always evaluated at the top level' do
        module Inner
            class Inner
                require 'test_top_level'
            end
        end

        if RUBY_VERSION[0..2] == '1.8'
        then
            Module.constants.should include('TestTopLevel')
        else
            Module.constants.should include(:TestTopLevel)
        end
    end
end

执行:

$ rspec --format nested ttl.rb 

require inside nested classes/modules
    (in TestTopLevel ...)
  is always evaluated at the top level

Finished in 0.0196 seconds
1 example, 0 failures

<强>乙
如果您不想处理不必要的require语句,则可以使用autoload。 autoload( name, file_name )在第一次访问模块名时注册要加载的file_name(使用Object#require)。

文件twitter_oauth.rb:

module TwitterOAuth
    class Client
        def initialize
            puts "hello from #{self}"
        end
    end
end

档案t.rb:

p Module.constants.sort.grep(/^T/)

class Foo
    puts "in class #{self.name}"

    autoload :TwitterOAuth, 'twitter_oauth'

    def bar_2
        puts 'in bar2'
        TwitterOAuth::Client.new
    end
end 

temp = Foo.new
puts 'about to send bar_2'
temp.bar_2

p Module.constants.sort.grep(/^T/)

在Ruby 1.8.6中执行:

$ ruby -w t.rb 
["TOPLEVEL_BINDING", "TRUE", "Thread", "ThreadError", "ThreadGroup", "Time", "TrueClass", "TypeError"]
in class Foo
about to send bar_2
in bar2
hello from #<TwitterOAuth::Client:0x10806d700>
["TOPLEVEL_BINDING", "TRUE", "Thread", "ThreadError", "ThreadGroup", "Time", "TrueClass", "TwitterOAuth", "TypeError"]