intersystems cache - Does object script supports multiple inheritance? -


i new cache , found different normal oop concept. in object script base class can inherited multiple subclasses(inheritance order can left/right). if objectscript oop, don't know how cache supports this(unlikely other programming language).

baseclass

  class inheritance.thebaseclass extends (%registeredobject,    inheritance.thechildclass, inheritance.thechildclass1) [ inheritance = left ]   {       classmethod init()      {       //do ##class(inheritance.thechildclass).ping()       //do ##class(inheritance.thechildclass1).ping()       ..ping()       ..pingggg()       }     }

child class 1

 class inheritance.thechildclass extends %registeredobject  {     classmethod ping()    {         write "i in inheritance.thechildclass",!     }   }

child class 2

class inheritance.thechildclass1 extends %registeredobject {    classmethod ping()   {     write "i in inheritance.thechildclass1",!   }    classmethod pingggg()   {     write "i in inheritance.thechildclass1111111111",!    }    }

output

i in inheritance.thechildclass

i in inheritance.thechildclass1111111111

documentation explains clearly: http://docs.intersystems.com/latest/csp/docbook/docbook.ui.page.cls?key=gobj_classes#gobj_classes_inheritance

for example, if class x inherits classes a, b, , c, definition includes:

class x extends (a, b, c)  { }

the default inheritance order class compiler left right, means differences in member definitions among superclasses resolved in favor of leftmost superclass (in case, superseding b , c, , b superseding c.)

specifically, class x, values of class parameter values, properties, , methods inherited class (the first superclass listed), class b, and, finally, class c. x inherits class members b has not defined, , class members c neither nor b has defined. if class b has class member same name member inherited a, x uses value a; similarly, if c has member same name 1 inherited either or b, order of precedence a, b, c.


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