bound-0.1.3: bound.cabal
name: bound
category: Language, Compilers/Interpreters
version: 0.1.3
license: BSD3
cabal-version: >= 1.6
license-file: LICENSE
author: Edward A. Kmett
maintainer: Edward A. Kmett <ekmett@gmail.com>
stability: experimental
homepage: http://github.com/ekmett/bound/
bug-reports: http://github.com/ekmett/bound/issues
copyright: Copyright (C) 2012 Edward A. Kmett
synopsis: Combinators for manipulating locally-nameless generalized de Bruijn terms
description:
The goal of this package is to make it as easy as possible to deal with name binding without forcing an
awkward monadic style on the user. To that end we provide haskell 98 combinators for manipulating
locally-nameless generalized de Bruijn terms, build over user-supplied term types. A generalized
de Bruijn term is one where you can 'succ' whole trees instead of just individual variables.
.
The approach was first elaborated in Bird and Patterson, \"de Bruijn notation as a nested data type\":
.
<http://www.cs.uwyo.edu/~jlc/courses/5000_fall_08/debruijn_as_nested_datatype.pdf>
.
However, the combinators they used required higher rank types. Here we use a monad transformer to encapsulate
the novel recursion pattern in their generalized de Bruijn representation. It is named Scope to match up
with the terminology from Conor McBride and James McKinna's \"I am not a number: I am a free variable\",
while providing stronger type safety guarantees.
.
<http://www.cs.st-andrews.ac.uk/~james/RESEARCH/notanum.pdf>
.
There are three worked examples in the examples folder:
.
* /Simple.hs/ provides an untyped lambda calculus with recursive let bindings.
.
* /Derived.hs/ shows how much of the API can be automated with DeriveTraversable
and adds combinators for building binders with pattern matching.
.
* /Overkill.hs/ provides very strongly typed pattern matching many modern type extensions, including
polymorphic kinds to ensure type safety. In general, the approach taken by Derived seems to deliver
a better power to weight ratio.
build-type: Simple
extra-source-files: .travis.yml examples/Simple.hs examples/Deriving.hs examples/Overkill.hs
source-repository head
type: git
location: git://github.com/ekmett/bound.git
library
build-depends:
base >= 4 && < 5,
bifunctors >= 0.1.3 && < 0.2,
prelude-extras >= 0.2 && < 0.3,
transformers >= 0.2 && < 0.4
exposed-modules:
Bound
Bound.Class
Bound.Scope
Bound.Term
Bound.Var
ghc-options: -Wall