数学中的链式法则
链式微分法则：
实数运算的链式法则：
对数运算的链式法则：
平行公理的链式法则：
向量运算的链式法则：
JS对象链式调用方法
ar obj = { test : function(){ alert("Y"); return this; }, test2 : function(){ alert("2"); return this; }}obj.test().test2(); // And so on since it returns this
lua OOP实现
--
-- Class helper routines
--
-- Instantiates a class
local function _instantiate(class, ...)
local inst = setmetatable({__class=class}, {__index = class})
if inst.__init__ then
inst:__init__(...)
end
return inst
end
--- Create a Class object (Python-style object model).
-- The class object can be instantiated by calling itself.
-- Any class functions or shared parameters can be attached to this object.
-- Attaching a table to the class object makes this table shared between
-- all instances of this class. For object parameters use the __init__ function.
-- Classes can inherit member functions and values from a base class.
-- Class can be instantiated by calling them. All parameters will be passed
-- to the __init__ function of this class - if such a function exists.
-- The __init__ function must be used to set any object parameters that are not shared
-- with other objects of this class. Any return values will be ignored.
-- @param base The base class to inherit from (optional)
-- @return A class object
-- @see instanceof
-- @see clone
function class(base)
-- __parent 属性缓存父类，便于子类索引父类方法
return setmetatable({__parent = base}, {
__call = _instantiate,
__index = base
})
end
--- Test whether the given object is an instance of the given class.
-- @param object Object instance
-- @param class Class object to test against
-- @return Boolean indicating whether the object is an instance
-- @see class
-- @see clone
function instanceof(object, class)
local meta = getmetatable(object)
while meta and meta.__index do
if meta.__index == class then
return true
end
meta = getmetatable(meta.__index)
end
return false
end
local ChainClass = class()
ChainClass.setFlag = function ( self, flag )
self.flag = flag
print("set flag = "..flag)
return self
end
ChainClass.setType = function ( self, type )
self.type = type
print("set type = "..type)
return self
end
ChainClass.printAttrs = function ( self, flag )
for k,v in pairs(self) do
print("name="..k.." value="..tostring(v))
end
return self
end
local chainObj = ChainClass()
chainObj:setFlag(1):setType(2):printAttrs()