Double dot?

double dot   ..property  is the shortcut for $this.property in instance methods.

http://docs.intersystems.com/latest/csp/docbook/DocBook.UI.Page.cls?KEY=...

http://docs.intersystems.com/latest/csp/docbook/DocBook.UI.Page.cls?KEY=...

not only properties. Also:

d ..AnotherMethod() // of THIS class

w ..#Parameter // of THIS class

and even 

d ..AnotherClassMethod()  //of course in ClassMethod or Method of THIS class

double dot - shortcut to THIS class context