The flexible-defaults package
Template Haskell code to implement default implementations for type-class functions based on which functions are already implemented. Currently extremely crude but still fairly effective.
When defining a type class with many functions, each of which can be implemented based on arbitrary subsets of the others, the standard default-implementation concept breaks down quite badly. This library provides a system by which more complex rules can be described for choosing default implementations based on which ones the user supplies. These implementations can additionally be given "suitability scores", so that when multiple possible choices could be made, the library can choose the "best" one.
Changes in v0.0.0.2: Nothing at all except setting 'buildable: False' under GHC 7.2.1. Technically it builds on 7.2.1, but it doesn't actually generate correct code due to http:hackage.haskell.orgtracghcticket5410 which has been patched and will almost certainly be fixed in the next GHC release. AFAIK 7.2.1 is the only release where this bug actually caused problems. I'm sure it could be worked around, but it's a whole lot easier to just say wait for 7.2.2/7.4. If anyone desperately needs this package under 7.2.1, let me know and I'll see what I can do.
|Versions||0.0.0.1, 0.0.0.2, 0.0.0.3, 0.0.1.0, 0.0.1.1|
|Change log||None available|
|Dependencies||base (>=3 && <5), containers, template-haskell, transformers [details]|
|Author||James Cook <email@example.com>|
|Maintainer||James Cook <firstname.lastname@example.org>|
|Category||Code Generation, Template Haskell|
|Source repository||head: git clone https://github.com/mokus0/flexible-defaults.git|
|Uploaded||Mon Aug 15 14:21:11 UTC 2011 by JamesCook|
|Distributions||Debian:0.0.1.1, LTSHaskell:0.0.1.1, NixOS:0.0.1.1, Stackage:0.0.1.1|
|Downloads||4761 total (8 in last 30 days)|
|Status||Docs uploaded by user|
Build status unknown [no reports yet]
- flexible-defaults-0.0.0.2.tar.gz [browse] (Cabal source package)
- Package description (included in the package)
For package maintainers and hackage trustees