ifcxt: put if statements within type constraints
This package introduces the ifCxt function,
which lets your write if statements that depend on a polymorphic variable's class instances.
For example, we can make a version of show that can be called on any type:
cxtShow :: forall a. IfCxt (Show a) => a -> String
cxtShow a = ifCxt (Proxy::Proxy (Show a))
(show a)
"<<unshowable>>"Running this function in ghci, we get:
>>>cxtShow (1 :: Int)"1"
>>>cxtShow (id :: a -> a)"<<unshowable>>"
See the project webpage http://github.com/mikeizbicki/ifcxt for more details.
| Versions [faq] | 0.1.0.0, 0.1.1 |
|---|---|
| Dependencies | base (==4.8.*), template-haskell (==2.10.*) [details] |
| License | BSD-3-Clause |
| Author | Mike Izbicki |
| Maintainer | mike@izbicki.me |
| Category | Control |
| Home page | http://github.com/mikeizbicki/ifcxt |
| Source repo | head: git clone http://github.com/mikeizbicki/ifcxt |
| Uploaded | by MikeIzbicki at 2016-08-03T21:52:43Z |
| Distributions | NixOS:0.1.1 |
| Downloads | 1371 total (5 in the last 30 days) |
| Rating | 2.25 (votes: 2) [estimated by Bayesian average] |
| Your Rating | |
| Status | Docs not available [build log] All reported builds failed as of 2016-11-21 [all 2 reports] |
Modules
- IfCxt
- IfCxt.Examples
Downloads
- ifcxt-0.1.1.tar.gz [browse] (Cabal source package)
- Package description (as included in the package)