A device that can record bass lines and the replay them live?

Subject:

Comments:
: I am looking for a device that can record bass lines and the replay these lines in a live situation. I am thinking that the songs would be broken up into three four, five, or six parts and the bass line would be recorded for each part. A foot pedal would be use to move from one bass part to another within a particular song. Ideally the device would have the capacity to record and play back up to 30 song at a time. Has anyone heard of or used such a device?