-- Hoogle documentation, generated by Haddock
-- See Hoogle, http://www.haskell.org/hoogle/


-- | Functional Pearl: Implicit Configurations
--   
--   This package provides an implementation of the ideas presented in the
--   paper <a>Functional Pearl: Implicit Configurations</a> by Oleg
--   Kiselyov and Chung-chieh Shan. However, the API has been modified to
--   use only one extension: <tt>Rank2Types</tt>
--   
--   Usage reduces to using two combinators.
--   
--   <pre>
--   reify :: a -&gt; (forall s. Reified s =&gt; Proxy (s a) -&gt; w) -&gt; w
--   reflect :: Reified s =&gt; p (s a) -&gt; a
--   </pre>
--   
--   <pre>
--   ghci&gt; reify 6 (\p -&gt; reflect p + reflect p)
--   12
--   </pre>
--   
--   The argument passed along by reify is just a <tt>data Proxy t =
--   Proxy</tt>, so all of the information needed to reconstruct your value
--   has been moved to the type level. This enables it to be used when
--   constructing instances (See <tt>examples/Monoid.hs</tt>). An
--   additional combinator that may be more useful when building instances
--   is also supplied.
--   
--   <pre>
--   reflectT :: Reified s =&gt; p s a -&gt; a
--   </pre>
--   
--   <i>Changes in 0.7</i>:
--   
--   <ul>
--   <li>Uses a much simpler construction where <tt>reify</tt> now converts
--   a <tt>StablePtr</tt> to an <tt>IntPtr</tt> and reifies that directly
--   as an integral type rather than serializing and storing the StablePtr
--   as a list of bytes as proposed in the original paper.</li>
--   <li>Removed <tt>ReifiedStorable</tt> and <tt>ReifiedNums</tt>.</li>
--   <li>Since we have so many fewer classes now,
--   <tt>Data.Reflection.Internal</tt> was merged back into
--   <tt>Data.Reflection</tt></li>
--   </ul>
--   
--   <i>Changes in 0.6</i>:
--   
--   <ul>
--   <li>Removed the dependency on multiparameter type classes, functional
--   dependencies, and flexible instances, by making <tt>Reifies</tt> a
--   single parameter type class in the same fashion as
--   <tt>ReifiesStorable</tt>.</li>
--   <li>Moved the building blocks to <tt>Data.Reflection.Internal</tt> to
--   reduce API clutter.</li>
--   <li>Added <tt>reflectT</tt></li>
--   </ul>
--   
--   <i>Changes in 0.5</i>:
--   
--   <ul>
--   <li>Generalized the type signatures in reflect to allow you to pass
--   any type with kind <tt>* -&gt; *</tt> wrapped around the desired type
--   as the phantom type argument rather than just a <tt>Proxy</tt>.</li>
--   </ul>
--   
--   <i>Changes in 0.4</i>:
--   
--   <ul>
--   <li>Converted from <a>Data.Tagged</a> to using <a>Data.Proxy</a> for
--   reflection. This reduces the need for helper functions and scoped type
--   variables in user code.</li>
--   </ul>
@package reflection
@version 0.7


-- | Based on the Functional Pearl: Implicit Configurations paper by Oleg
--   Kiselyov and Chung-chieh Shan.
--   
--   <a>http://www.cs.rutgers.edu/~ccshan/prepose/prepose.pdf</a>
--   
--   Modified to minimize extensions and work with Data.Proxy rather than
--   explicit scoped type variables and undefined values by Edward Kmett.
module Data.Reflection
class Reified s
reflect :: Reified s => p (s a) -> a
reify :: a -> (forall s. Reified s => Proxy (s a) -> w) -> w
reflectT :: Reified s => t s a -> a
class ReifiedNum s
reflectNum :: (ReifiedNum s, Num a) => proxy s -> a
reifyIntegral :: Integral a => a -> (forall s. ReifiedNum s => Proxy s -> w) -> w
instance Show Zero
instance Show (Twice s)
instance Show (SuccTwice s)
instance Show (PredTwice s)
instance ReifiedNum s => Reified (Stable s)
instance ReifiedNum s => ReifiedNum (PredTwice s)
instance ReifiedNum s => ReifiedNum (SuccTwice s)
instance ReifiedNum s => ReifiedNum (Twice s)
instance ReifiedNum Zero