| OddNumberBytesException | Michelson.Parser.Error, Michelson.Parser |
| offshoot | Michelson.Test.Integrational, Lorentz.Test.Integrational, Lorentz.Test |
| OneField | Michelson.Typed.Haskell.Instr.Sum, Michelson.Typed.Haskell.Instr, Michelson.Typed.Haskell, Michelson.Typed |
| onLeft | Michelson.TypeCheck.Helpers |
| onTypeCheckInstrAnnErr | Michelson.TypeCheck.Helpers |
| onTypeCheckInstrErr | Michelson.TypeCheck.Helpers |
| ooBalance | Michelson.Untyped.Instr, Michelson.Untyped |
| ooContract | Michelson.Untyped.Instr, Michelson.Untyped |
| ooDelegate | Michelson.Untyped.Instr, Michelson.Untyped |
| ooOriginator | Michelson.Untyped.Instr, Michelson.Untyped |
| ooStorage | Michelson.Untyped.Instr, Michelson.Untyped |
| opAbsense | Michelson.Typed.Scope, Michelson.Typed |
| OpAbsent | Michelson.Typed.Scope, Michelson.Typed |
| OpCreateContract | Michelson.Typed.Value, Michelson.Typed |
| Operation | Michelson.Typed.Aliases, Michelson.Typed, Lorentz.Value, Lorentz |
| Operation' | Michelson.Typed.Value, Michelson.Typed |
| OpPresence | Michelson.Typed.Scope, Michelson.Typed |
| OpPresent | Michelson.Typed.Scope, Michelson.Typed |
| ops' | Michelson.Parser.Instr |
| OpSetDelegate | Michelson.Typed.Value, Michelson.Typed |
| OpSize | |
| 1 (Type/Class) | Michelson.OpSize |
| 2 (Data Constructor) | Michelson.OpSize |
| opSizeHardLimit | Michelson.OpSize |
| optimize | Michelson.Optimizer |
| optimizeLorentz | Lorentz.Base, Lorentz |
| optimizeLorentzWithConf | Lorentz.Base, Lorentz |
| OptimizerConf | |
| 1 (Type/Class) | Michelson.Optimizer |
| 2 (Data Constructor) | Michelson.Optimizer |
| optimizeWithConf | Michelson.Optimizer |
| OpTransferTokens | Michelson.Typed.Value, Michelson.Typed |
| OR | |
| 1 (Data Constructor) | Michelson.Untyped.Instr, Michelson.Untyped |
| 2 (Data Constructor) | Michelson.Typed.Instr, Michelson.Typed |
| Or | Michelson.Typed.Arith, Michelson.Typed |
| or | Lorentz.Instr, Lorentz |
| orAnn | Michelson.Typed.Annotation, Michelson.Typed |
| Ord | Lorentz.Prelude, Lorentz |
| originate | Michelson.Test.Integrational, Michelson.Test |
| originateContract | Michelson.Runtime |
| OriginateOp | Michelson.Runtime |
| OriginationOperation | |
| 1 (Type/Class) | Michelson.Untyped.Instr, Michelson.Untyped |
| 2 (Data Constructor) | Michelson.Untyped.Instr, Michelson.Untyped |
| orRule | Michelson.Optimizer |
| orSimpleRule | Michelson.Optimizer |
| ourIngredients | Util.Test.Ingredients |
| outPattern | Michelson.Untyped.Ext, Michelson.Untyped |