书 ruby for rails（2007 年出版） ruby script/generate model work 报错： ruby: No such file or directory -- script/generate (LoadError) 把命令改为：rails generate model work 报错：~/ruby/R4Rmusic$ rails generate model work /home/liuchao/.rvm/gems/ruby-2.1.0/gems/railties-4.1.0.beta1/lib/rails/application/configuration.rb:103:in `rescue in database_configuration': YAML syntax error occurred while parsing /home/liuchao/ruby/R4Rmusic/config/database.yml. Please note that YAML must be consistently indented using spaces. Tabs are not allowed. Error: (): could not find expected ':' while scanning a simple key at line 3 column 1 (RuntimeError)