In the examples above, the input signals were usually defined implicitly by the defining FAUST expression:
foo = faust_expression; // inputs and outputs determined by expressionSometimes, however, it is helpful to fix the number of input signals. For example, to define a stereo processor, one can begin and end its definition with two wires:
foo = _,_ : faust_expression : _,_;Such practice also helps to more easily catch errors when the number of input or output signals comes out wrong in the defining expression.