The syb package

[ Tags: bsd3, generics, library ] [ Propose Tags ]

This package contains the generics system described in the Scrap Your Boilerplate papers (see It defines the Data class of types permitting folding and unfolding of constructor applications, instances of this class for primitive types, and a variety of traversals.

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Versions,,,, 0.2, 0.2.1, 0.2.2, 0.3, 0.3.1, 0.3.2, 0.3.3, 0.3.4, 0.3.5, 0.3.6,,, 0.3.7, 0.4.0, 0.4.1, 0.4.2, 0.4.3, 0.4.4, 0.5, 0.5.1, 0.6, 0.7
Dependencies base (>=4.5 && <4.8) [details]
License BSD3
Author Ralf Lammel, Simon Peyton Jones, Jose Pedro Magalhaes
Category Generics
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Source repo head: git clone
Uploaded Sun May 31 14:29:27 UTC 2015 by JosePedroMagalhaes
Updated Mon Jun 1 09:32:59 UTC 2015 by AdamBergmark to revision 1   [What is this?]
Distributions Arch:0.7, Debian:0.6, Fedora:0.7, FreeBSD:0.5.1, LTSHaskell:0.7, NixOS:0.7, Stackage:0.7, openSUSE:0.7
Downloads 274676 total (410 in the last 30 days)
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Status Docs available [build log]
Last success reported on 2015-06-08 [all 1 reports]
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Note: This package has metadata revisions in the cabal description newer than included in the tarball. To unpack the package including the revisions, use 'cabal get'.

Maintainer's Corner

For package maintainers and hackage trustees

Readme for syb-0.5

[back to package description]
syb: Scrap Your Boilerplate!

Scrap Your Boilerplate (SYB) is a library for generic programming in Haskell. It 
is supported since the GHC >= 6.0 implementation of Haskell. Using this 
approach, you can write generic functions such as traversal schemes (e.g., 
everywhere and everything), as well as generic read, generic show and generic 
equality (i.e., gread, gshow, and geq). This approach is based on just a few 
primitives for type-safe cast and processing constructor applications. 

It was originally developed by Ralf Lämmel and Simon Peyton Jones. Since then,
many people have contributed with research relating to SYB or its applications. 

More information is available on the webpage:


* Easy generic programming with combinators
* GHC can derive Data and Typeable instances for your datatypes
* Comes with many useful generic functions


* GHC 6.10.1 or later
* Cabal 1.6 or later

Bugs & Support

Please report issues or request features at the bug tracker:

For discussion about the library with the authors, maintainers, and other
interested persons use the mailing list: