製作引擎：未找到庫類：未初始化常數（NameError）

「/lib/gem_name/resource.rb」

module GemName 
    class Resource 
    def initialize 
     # nothing 
    end 
    end 
end

和「/ LIB/gem_name.rb /test/dummy/config/initializers/gem_name.rb」

require "gem_name/engine" 

module GemName 
    def new_resource 
    @resources << GemName::Resource.new 
    end 
end

在

「」

GemName.new_resource

當我啓動控制檯，顯示此消息：

unitialized constant GemName::Resource (NameError)

我檢查gem_name.gemspec，其內容是：

$:.push File.expand_path("../lib", __FILE__) 

# Maintain your gem's version: 
require "gem_name/version" 

# Describe your gem and declare its dependencies: 
Gem::Specification.new do |s| 
    s.name  = "gem_name" 
    s.version  = GemName::VERSION 
    s.authors  = ["TODO: Your name"] 
    s.email  = ["TODO: Your email"] 
    s.homepage = "TODO" 
    s.summary  = "TODO: Summary of GemName." 
    s.description = "TODO: Description of GemName." 

    s.files = Dir["{app,config,db,lib}/**/*"] + ["MIT-LICENSE", "Rakefile", "README.rdoc"] 
    s.test_files = Dir["test/**/*"] 

    s.add_dependency "rails", "~> 3.2.8" 
    # s.add_dependency "jquery-rails" 

    s.add_development_dependency "sqlite3" 
end

環境規格：