Another strategy to make life easier is to separate data flow (the transformation of inputs to outputs) and control flows. The control flow knows the context, a

Another strategy to make life easier is to separate data flow (the transformation of inputs to outputs) and control flows. The control flow knows the context, and given the current state decides how the data flow transformation is performed. Think of an ALU that can perform add, sub, shift operations. The ALU implementation simply accepts operands and perform one of the supported operations to generate the output. The control flow would in this case look at an opcode and decide which of the ALU operations to perform.