| Unknown | Haskore.Interface.MIDI, Haskore.Interface.MIDI.File |
| UpBow | Haskore.Music |
| UpdateContext | Haskore.Music.Performance |
| uniform | Haskore.Interface.CSound.Score |
| unison | Haskore.Basic.Interval |
| unlinesS | Haskore.General.Utility |
| updateCSound | Main |
| updateDur | Haskore.Music.Performance, Haskore.Music.PerformanceContext |
| updateInstrument | Haskore.Music.Performance, Haskore.Music.PerformanceContext |
| updateKey | Haskore.Music.Performance, Haskore.Music.PerformanceContext |
| updatePlayer | Haskore.Music.Performance, Haskore.Music.PerformanceContext |
| updateTime | Haskore.Music.Performance, Haskore.Music.PerformanceContext |
| updateVelocity | Haskore.Music.Performance, Haskore.Music.PerformanceContext |
| upm | Haskore.Example.Kantate147 |
| usedInstruments | Haskore.Music.Performance |
