<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>Control.Monad.Trans</title><link href="ocean.css" rel="stylesheet" type="text/css" title="Ocean" /><script src="haddock-util.js" type="text/javascript"></script><script type="text/javascript">//<![CDATA[
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</script></head><body><div id="package-header"><ul class="links" id="page-menu"><li><a href="src/Control-Monad-Trans.html">Source</a></li><li><a href="index.html">Contents</a></li><li><a href="doc-index.html">Index</a></li></ul><p class="caption">mtl-2.0.1.0: Monad classes, using functional dependencies</p></div><div id="content"><div id="module-header"><table class="info"><tr><th>Portability</th><td>portable</td></tr><tr><th>Stability</th><td>experimental</td></tr><tr><th>Maintainer</th><td>libraries@haskell.org</td></tr></table><p class="caption">Control.Monad.Trans</p></div><div id="description"><p class="caption">Description</p><div class="doc"><p>Classes for monad transformers.
</p><p>A monad transformer makes new monad out of an existing monad, such
that computations of the old monad may be embedded in the new one.
To construct a monad with a desired set of features, one typically
starts with a base monad, such as <code>Identity</code>, <code>[]</code> or <code><a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-IO.html#t:IO">IO</a></code>, and
applies a sequence of monad transformers.
</p><p>Most monad transformer modules include the special case of applying the
transformer to <code>Identity</code>. For example, <code>State s</code> is an abbreviation
for <code>StateT s Identity</code>.
</p><p>Each monad transformer also comes with an operation <code>run</code><em>XXX</em> to
unwrap the transformer, exposing a computation of the inner monad.
</p></div></div><div id="interface"><h1>Documentation</h1><div class="top"><p class="src">module <a href="/usr/share/doc/ghc/html/libraries/transformers-0.2.2.0/Control-Monad-Trans-Class.html">Control.Monad.Trans.Class</a></p></div><div class="top"><p class="src">module <a href="/usr/share/doc/ghc/html/libraries/transformers-0.2.2.0/Control-Monad-IO-Class.html">Control.Monad.IO.Class</a></p></div></div></div><div id="footer"><p>Produced by <a href="http://www.haskell.org/haddock/">Haddock</a> version 2.9.2</p></div></body></html>
