edit: A monad for rewriting things.
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Properties
| Versions | 0.0.1.0, 0.0.1.1, 0.0.1.1, 1.0.0.0, 1.0.1.0 |
|---|---|
| Change log | ChangeLog.md |
| Dependencies | base (>=4.9 && <4.12), deepseq (>=1.1 && <1.5), transformers (>=0.5 && <0.6) [details] |
| License | BSD-3-Clause |
| Copyright | Varun Gandhi 2018 |
| Author | Varun Gandhi <theindigamer15@gmail.com> |
| Maintainer | Varun Gandhi <theindigamer15@gmail.com> |
| Category | Data |
| Home page | https://github.com/theindigamer/edit |
| Source repo | head: git clone https://github.com/theindigamer/edit.git |
| Uploaded | by theindigamer at 2018-05-28T16:51:20Z |
Modules
[Index]
- Control
- Monad
- Data
Flags
Manual Flags
| Name | Description | Default |
|---|---|---|
| arbitrary_instance | Adds QuickCheck as a dependency to provide an Arbitrary instance. | Disabled |
| comonad_instance | Adds comonad as a dependency to provide a Comonad instance. | Disabled |
| tutorial | Build the tutorial. Adds dependencies on uniplate and containers. | Disabled |
Use -f <flag> to enable a flag, or -f -<flag> to disable that flag. More info
Downloads
- edit-0.0.1.1.tar.gz [browse] (Cabal source package)
- Package description (as included in the package)
Maintainer's Corner
Package maintainers
For package maintainers and hackage trustees
Readme for edit-0.0.1.1
[back to package description]Edit 
The Edit monad allows you to easily bubble up whether a change was made or
not when rewriting things. Some cases where this can be handy:
- You are making a sequence of transformations on some type and want to keep track of whether any of them changed it or not.
- You are rewriting a recursive type and want to bubble up information whether something was changed or not.
A small example:
>>> halveEvens x = if x `mod` 2 == 0 then (Dirty $ x `div` 2) else (Clean x)
>>> traverse halveEvens [1, 2, 3]
Dirty [1,1,3]
>>> traverse halveEvens [1, 3, 5]
Clean [1,3,5]
More thorough documentation is available on Hackage
under the Data.Edit module. There is a tutorial too under Data.Edit.Tutorial.
There is also a corresponding monad transformer EditT available under Control.Monad.Trans.EditT.
Contributing
Please open an issue on the Github issue tracker to discuss missing documentation, API changes etc.