README.md

flippre: FliPpr, embedded

flippre is an embedded implementation of FliPpr, an invertible pretty-printing system. The library provides functions and datatypes that enable you to define pretty-printers in a functional programming style while ensuring they remain invertible to produce context-free grammar (CFG) parsers. (The current implementation relies on the Earley library for parsing.)

This repository consists of four packages:

• flippre: The embedded FliPpr system.
• flippre-examples: Examples of invertible pretty-printers defined using FliPpr.
• flippre-grammar-backend: Internally used for grammar processing within FliPpr.
• mutual-def-class: Internally used for observable mutually recursive definitions.

Build Instructions

You can build the project using either stack or cabal.

Using stack:

stack build

Using cabal

cabal build all

Examples

You can find examples in the flippre-examples directory. For instance, For instance, Arith.hs demonstrates an invertible pretty-printer for simple arithmetic expressions. You can experiment with these examples in a REPL as follows:

Using stack:

stack repl flippre-examples:exe:arith 

Using cabal:

cabal repl arith

Publications

• Kazutaka Matsuda, Meng Wang: Embedding invertible languages with binders: a case of the FliPpr language. Haskell Symposium 2018: 158-171
• Kazutaka Matsuda, Meng Wang: FliPpr: A System for Deriving Parsers from Pretty-Printers. New Generation Computing 36(3): 173-202 (2018)
• Kazutaka Matsuda, Meng Wang: FliPpr: A Prettier Invertible Printing System. ESOP 2013: 101-120