1. A medical pump system that provides advance guidance to a user regarding existence and non-existence of a valid input range for a pump programming parameter, comprising: an input device for entering a value of a pump programming parameter; a memory for storing constraints related to the pump programming parameter; a processor in communication with the memory and the input device, the processor being operable to utilize the constraints to determine and generate a signal, determined from among an affirmative signal and a negative signal, indicating whether a valid input range exists for a to-be-entered value of the pump programming parameter; and an output device in communication with the processor to receive the signal indicating whether a valid input range exists for a to-be-entered value of the pump programming parameter and, for both a determination that the signal is the affirmative signal and a determination that the signal is the negative signal, explicitly generate a notification to a user of the medical pump system based on the signal immediately prior to attempted input of the to-be-entered value of the pump programming parameter.