Copyright (C) 1994, Digital Equipment Corp.
<* PRAGMA LL *>
<* PRAGMA SUBTYPE *>
A BiFeedbackVBT is a multi-filter feedback that is used for
composing two arbitrary feedbacks. The default normal and
excited methods of a BiFeedbackVBT invoke the corresponding
methods on the two feedbacks. The BiFeedbackVBT itself doesn't
have any visual appearance.
INTERFACE BiFeedbackVBT;
IMPORT FeedbackVBT, VBT;
TYPE
<* SUBTYPE T <: MultiFilter.T *>
T <: Public;
Public = FeedbackVBT.T OBJECT
METHODS
<* LL <= VBT.mu *>
init (f1, f2: FeedbackVBT.T; ch: VBT.T): T;
END;
The call v.init(f1, f2, ch) initializes v as a BiFeedbackVBT.
The multi-child of v is ch. The internal structure of v is
as follows: The VBT-child of v is f1, the multi-child of f1
is f2, and the multi-child of f2 is ch. (Recall that it is
legal and meaningful for a VBT to have multiple multi-parents, as
ch will have.) When the init method is called, both f1 and
f2 must be childless.
END BiFeedbackVBT.