The keyword Self is used in the definition of a Variable to refer to that variable.
Usually, a variable cannot refer to itself -- because it creates a cyclic dependency -- so you cannot use Self in common expressions. One exception is in the Dynamic function when referring to Self at a preceding Time period, e.g.
Variable X := Dynamic(10, Self[Time - 1]*(1 + growth))
The last parameter of Dynamic is an expression that can refer to Self, provided it is for a previous Time, as in this case.
The other exception is in IntraTable that allows cells of a table to refer to each other, using Self.
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