| L1 | Protolude |
| Last | |
| 1 (Data Constructor) | Protolude |
| 2 (Type/Class) | Protolude |
| lastDef | Protolude.Safe, Protolude |
| lastMay | Protolude.Safe, Protolude |
| LByteString | Protolude |
| lcm | Protolude.Base, Protolude |
| Left | Protolude |
| LeftAssociative | Protolude |
| lefts | Protolude |
| leftToMaybe | Protolude.Either, Protolude |
| length | Protolude |
| Leniency | Protolude.Conv, Protolude |
| Lenient | Protolude.Conv, Protolude |
| lenientDecode | Protolude |
| lift | Protolude |
| liftA | Protolude |
| liftA2 | Protolude |
| liftA3 | Protolude |
| liftAA2 | Protolude.Applicative, Protolude |
| liftIO | Protolude |
| liftIO1 | Protolude |
| liftIO2 | Protolude |
| liftM | Protolude.Monad, Protolude |
| liftM' | Protolude.Monad, Protolude |
| liftM2 | Protolude.Monad, Protolude |
| liftM2' | Protolude.Monad, Protolude |
| liftM3 | Protolude.Monad, Protolude |
| liftM4 | Protolude.Monad, Protolude |
| liftM5 | Protolude.Monad, Protolude |
| lines | Protolude |
| link | Protolude |
| link2 | Protolude |
| list | Protolude.List, Protolude |
| listToMaybe | Protolude |
| local | Protolude |
| Location | |
| 1 (Data Constructor) | Protolude.Base, Protolude |
| 2 (Type/Class) | Protolude.Base, Protolude |
| log | Protolude.Base, Protolude |
| log1mexp | Protolude.Base, Protolude |
| log1p | Protolude.Base, Protolude |
| log1pexp | Protolude.Base, Protolude |
| logBase | Protolude.Base, Protolude |
| LossOfPrecision | Protolude |
| LT | Protolude |
| LText | Protolude |