https://github.com/carstenkoenig/gadtparser

parsing GADT-style expression trees
https://github.com/carstenkoenig/gadtparser

doctest generalized-algebraic-data-type haskell megaparsec parsing

Last synced: 13 days ago
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parsing GADT-style expression trees

• Host: GitHub
• URL: https://github.com/carstenkoenig/gadtparser
• Owner: CarstenKoenig
• License: bsd-3-clause
• Created: 2019-08-22T11:59:33.000Z (over 5 years ago)
• Default Branch: master
• Last Pushed: 2019-08-22T12:00:02.000Z (over 5 years ago)
• Last Synced: 2024-11-29T17:45:10.809Z (2 months ago)
• Topics: doctest, generalized-algebraic-data-type, haskell, megaparsec, parsing
• Language: Haskell
• Size: 23.4 KB
• Stars: 3
• Watchers: 2
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

Awesome Lists containing this project

README

        
# GADT Parser

simple but complete example on how to parse GADT-style expressions

```haskell

data Expr (res :: Type) where

  IntE    :: Int -> Expr Int

  AddE    :: Expr Int -> Expr Int -> Expr Int

  BoolE   :: Bool -> Expr Bool

  IsNullE :: Expr Int -> Expr Bool

  IfE     :: Expr Bool -> Expr res -> Expr res -> Expr res

```

using [Megaparsec](https://www.stackage.org/haddock/lts-14.2/megaparsec-7.0.5/Text-Megaparsec.html)

see the [GADT-Module](./src/lib/GADT) for details.

There is also a simple [ADT implementation](./src/lib/ADT) for comparision.

## Build / Run / Test

This repository uses [hpack](https://hackage.haskell.org/package/hpack) and is tested with [stack](https://docs.haskellstack.org/en/stable/README/).

- Clone this repository

- `cd` into the project folder

- run 

  - `stack build` to build

  - `stack run` to run a simple "REPL" for the DSL

  - `stack test` to run the parser specs and doctests

  

I tried to document the modules so `stack haddock --open` should give you a nice

looking documentation.