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


-- | Reifies arbitrary terms into types that can be reflected back into terms
--   
--   This package provides an implementation of the ideas presented in the
--   paper "Functional Pearl: Implicit Configurations" by Oleg Kiselyov and
--   Chung-chieh Shan. However, the API has been streamlined to improve
--   performance.
--   
--   The original paper can be obtained from
--   <a>http://www.cs.rutgers.edu/~ccshan/prepose/prepose.pdf</a>.
--   
--   <i>Changes in 1.1.6</i>:
--   
--   <ul>
--   <li>Relaxed an unnecessary strictness annotation in the fast
--   implementation</li>
--   </ul>
--   
--   <i>Changes in 1.1.5</i>:
--   
--   <ul>
--   <li>Both implementations now work on Hugs; the fast implementation
--   ascends from the ranks of completely unportable black magic to being
--   merely <i>mostly</i> unportable black magic.</li>
--   </ul>
--   
--   <i>Changes from 0.5 to 1.1</i>:
--   
--   <ul>
--   <li>Much faster implementation available that is about 50 <i>times</i>
--   faster than 0.9 and which runs purely on black magic. This version is
--   now used by default. To turn it off install with the <tt>slow</tt>
--   flag. If you encounter a problem with the implementation, please
--   contact the author.</li>
--   <li>Removed <tt>ReifiedNum</tt>, <tt>reflectNum</tt>, and
--   <tt>reifyIntegral</tt>; <tt>reify</tt> and <tt>reflect</tt> are about
--   3 orders of magnitude faster than the special case combinators
--   were.</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 1.1.6


-- | Reifies arbitrary terms at the type level. 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>
--   
--   The approach from the paper was modified to work with Data.Proxy and
--   to cheat by using knowledge of GHC's internal representations by
--   Edward Kmett and Elliott Hird.
--   
--   Usage comes down to two combinators, <a>reify</a> and <a>reflect</a>.
--   
--   <pre>
--   &gt;&gt;&gt; reify 6 (\p -&gt; reflect p + reflect p)
--   12
--   </pre>
--   
--   The argument passed along by reify is just a <tt>data <a>Proxy</a> 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>).
module Data.Reflection
class Reifies s a | s -> a
reflect :: Reifies s a => proxy s -> a

-- | Reify a value at the type level, to be recovered with <a>reflect</a>.
reify :: a -> (forall s. Reifies s a => Proxy s -> r) -> r