Ormolu is a formatter for Haskell source code. The project was created with the following goals in mind:
- Using GHC’s own parser to avoid parsing problems caused by haskell-src-exts.
- Let some whitespace be programmable. The layout of the input influences the layout choices in the output. This means that the choices between single-line/multi-line layouts in certain situations are made by the user, not by an algorithm. This makes the implementation simpler and leaves some control to the user while still guaranteeing that the formatted code is stylistically consistent.
- Writing code in such a way so it’s easy to modify and maintain.
- Implementing one “true” formatting style which admits no configuration.
- The formatting style aims to result in minimal diffs.
- Choose a style compatible with modern dialects of Haskell. As new Haskell extensions enter broad use, we may change the style to accommodate them.
- Idempotence: formatting already formatted code doesn’t change it.
- Be well-tested and robust so that the formatter can be used in large projects.
This is free and open source software.
Website: github.com/tweag/ormolu
Support:
Developer: Tweag I/O
License: BSD License
Ormolu is written in Haskell. Learn Haskell with our recommended free books and free tutorials.
Related Software
| Haskell Linters | |
|---|---|
| Ormolu | Formatter for Haskell source code |
| HLint | Suggests improvements to Haskell code |
| Fourmolu | Formatter for Haskell source code, fork of Ormolu |
| stylish-haskell | Simple Haskell code prettifier |
| hindent | Extensible Haskell pretty printer |
| Stan | Haskell STatic ANalyser |
| Floskell | Flexible Haskell source code pretty printer |
| Weeder | Perform whole-program dead-code analysis |
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