平台:Mac OSX 10.6
在我的终端中,我用"rails c"启动Ruby控制台
在遵循Ruby on Rails 3教程构建类时:
class Word < String
def palindrome? #check if a string is a palindrome
self == self.reverse
end
end
我收到了错误信息:
TypeError: superclass mismatch for class Word
from (irb):33
from /Users/matthew/.rvm/gems/ruby-1.9.2-p180@rails3tutorial/gems/railties-3.0.5/lib/rails/commands/console.rb:44:in `start'
from /Users/matthew/.rvm/gems/ruby-1.9.2-p180@rails3tutorial/gems/railties-3.0.5/lib/rails/commands/console.rb:8:in `start'
from /Users/matthew/.rvm/gems/ruby-1.9.2-p180@rails3tutorial/gems/railties-3.0.5/lib/rails/commands.rb:23:in `<top (required)>'
from script/rails:6:in `require'
from script/rails:6:in `<main>'
教程显示它没有问题,我知道代码很好;我搜索了其他相关的问题,但它们都涉及从Ruby 2迁移到Ruby 3或erb与eruby.