有没有办法只获得Ruby类的类方法

Question

我用：

1.9.3-p448 :057 > Object.methods
 => 270 
1.9.3-p448 :058 > Object.instance_methods
 => 153

但是有没有办法得到类方法：

1.9.3-p448 :058 > Object.class_methods

我知道我可以：

1.9.3-p448 :057 > Object.methods - Object.instance_methods

但是有办法直接获得它们吗？ 另外，除了后者中的类方法之外，还有什么可能吗？

谢谢

Answer 1

klass.methods给出了klass类的类方法。

Dir.methods
# => [:open, :foreach, :entries, :chdir, :getwd, :pwd, :chroot, :mkdir, :rmdir,
:delete, :unlink, :home, :glob, :[], :exist?, :exists?, :allocate, :new,
:superclass, :freeze, :===, :==, :<=>, :<, :<=, :>, :>=, :to_s, :inspect,
:included_modules, :include?, :name, :ancestors, :instance_methods,
:public_instance_methods, :protected_instance_methods, :private_instance_methods,
:constants, :const_get, :const_set, :const_defined?, :const_missing,
:class_variables, :remove_class_variable, :class_variable_get,
:class_variable_set, :class_variable_defined?, :public_constant,
:private_constant, :module_exec, :class_exec, :module_eval, :class_eval,
:method_defined?, :public_method_defined?, :private_method_defined?,
:protected_method_defined?, :public_class_method, :private_class_method,
:autoload, :autoload?, :instance_method, :public_instance_method, :nil?, :=~,
:!~, :eql?, :hash, :class, :singleton_class, :clone, :dup, :taint, :tainted?,
:untaint, :untrust, :untrusted?, :trust, :frozen?, :methods, :singleton_methods,
:protected_methods, :private_methods, :public_methods, :instance_variables,
:instance_variable_get, :instance_variable_set, :instance_variable_defined?,
:remove_instance_variable, :instance_of?, :kind_of?, :is_a?, :tap, :send,
:public_send, :respond_to?, :extend, :display, :method, :public_method,
:define_singleton_method, :object_id, :to_enum, :enum_for, :equal?, :!, :!=,
:instance_eval, :instance_exec, :__send__, :__id__]

klass.methods(false)给出了类方法klass被上直接定义klass 。

Dir.methods(false)
# => [:open, :foreach, :entries, :chdir, :getwd, :pwd, :chroot, :mkdir, :rmdir,
:delete, :unlink, :home, :glob, :[], :exist?, :exists?]

Answer 2

Object.singleton_class.instance_methods

Answer 3

这应该可以解决问题：

YourObject.class.methods