Ruby Metaprogramming方法列表？

Question

刚开始学习Ruby元编程.看看Object.methods我得到:

Object.methods => [
:allocate, 
:new, 
:superclass, 
:freeze, 
:===, 
:==, 
:<=>, 
:<, 
:<=, 
:>, 
:>=, 
:to_s, 
: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?, 
: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, 
:initialize_dup, 
:initialize_clone, 
:taint, 
:tainted?, 
:untaint, 
:untrust, 
:untrusted?, 
:trust, 
:frozen?, 
:inspect, 
:methods, 
:singleton_methods, 
:protected_methods, 
:private_methods, 
:public_methods, 
:instance_variables, 
:instance_variable_get, 
:instance_variable_set, 
:instance_variable_defined?, 
:instance_of?, 
:kind_of?, 
:is_a?, 
:tap, 
:send, 
:public_send, 
:respond_to?, 
:respond_to_missing?, 
:extend, 
:display, 
:method, 
:public_method, 
:define_singleton_method, 
:__id__, 
:object_id, 
:to_enum, 
:enum_for, 
:equal?, 
:!, 
:!=, 
:instance_eval, 
:instance_exec, 
:__send__]

是否有一个对元编程有用的方法列表？如instance_eval,initialize和method_missing？

Answer 1

下面是从顶端回答这个页面:

方法相关的钩子

method_missing
method_added
singleton_method_added
method_removed
singleton_method_removed
method_undefined
singleton_method_undefined

类和模块挂钩

inherited
append_features
included
extend_object
extended
initialize_copy
const_missing

编组挂钩

marshal_dump
marshal_load

强制钩子

coerce
induced_from
to_xxx

另外,请查看此博客文章,了解其中许多方法的说明和示例代码.

Answer 2

Object是一个类,因此您列出的大多数方法实际上是Class实例方法.看看Object.private_methods- 你会发现define_method,这是绝对必要的.但是它binding也非常强大......在学习Ruby元编程时,你会想要查看Binding该类的文档.的send,__send__和public_send家人也是必不可少的.

查看上面的列表,您应该能够识别"反射"方法,这些方法可用于以编程方式查询和操作常量,方法,实例变量等.然后是eval和exec方法.method_missing是你学习的第一个,但const_missing也要注意.一定要检查set_trace_func和trace_var.而且我们会在哪里不alias和alias_method？

再就是翻译的"钩子"状method_added,method_removed,method_undefined,inherited,extended,included,singleton_method_added,singleton_method_removed,singleton_method_undefined,instance_method_added,instance_method_removed,和instance_method_undefined.

Object#method获取Method物品至关重要.看看所有的方法Method,包括像owner.Kernel#caller有时可能很有用.然后还要查看ObjectSpace课程.

理解虽然它们有一些特殊的行为,但类和模块只是对象,您可以动态创建它们,将它们存储在数据结构中等等.它们甚至不必具有名称.您只需拨打Class.new,使一个新的和使用class_eval,define_method根据需要方法添加到它,等等.

__LINE__并且__FILE__可能很有趣,尤其如此File.read(__FILE__).

理解块和lambdas对于一般的Ruby编程和特别是元编程都很重要.