<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html>
<head>
<!-- Generated by HsColour, http://www.cs.york.ac.uk/fp/darcs/hscolour/ -->
<title>Control/Concurrent/MVar/Lifted.hs</title>
<link type='text/css' rel='stylesheet' href='hscolour.css' />
</head>
<body>
<pre><a name="line-1"></a><span class='hs-comment'>{-# LANGUAGE CPP
<a name="line-2"></a> , UnicodeSyntax
<a name="line-3"></a> , NoImplicitPrelude
<a name="line-4"></a> , FlexibleContexts
<a name="line-5"></a> , TupleSections
<a name="line-6"></a> #-}</span>
<a name="line-7"></a>
<a name="line-8"></a><span class='hs-comment'>{- |
<a name="line-9"></a>Module : Control.Concurrent.MVar.Lifted
<a name="line-10"></a>Copyright : Bas van Dijk
<a name="line-11"></a>License : BSD-style
<a name="line-12"></a>
<a name="line-13"></a>Maintainer : Bas van Dijk <v.dijk.bas@gmail.com>
<a name="line-14"></a>Stability : experimental
<a name="line-15"></a>
<a name="line-16"></a>This is a wrapped version of 'Control.Concurrent.MVar' with types generalized
<a name="line-17"></a>from @IO@ to all monads in either 'MonadBase' or 'MonadBaseControl'.
<a name="line-18"></a>-}</span>
<a name="line-19"></a>
<a name="line-20"></a><span class='hs-keyword'>module</span> <span class='hs-conid'>Control</span><span class='hs-varop'>.</span><span class='hs-conid'>Concurrent</span><span class='hs-varop'>.</span><span class='hs-conid'>MVar</span><span class='hs-varop'>.</span><span class='hs-conid'>Lifted</span>
<a name="line-21"></a> <span class='hs-layout'>(</span> <span class='hs-conid'>MVar</span><span class='hs-varop'>.</span><span class='hs-conid'>MVar</span>
<a name="line-22"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>newEmptyMVar</span>
<a name="line-23"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>newMVar</span>
<a name="line-24"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>takeMVar</span>
<a name="line-25"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>putMVar</span>
<a name="line-26"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>readMVar</span>
<a name="line-27"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>swapMVar</span>
<a name="line-28"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>tryTakeMVar</span>
<a name="line-29"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>tryPutMVar</span>
<a name="line-30"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>isEmptyMVar</span>
<a name="line-31"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>withMVar</span>
<a name="line-32"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>modifyMVar_</span>
<a name="line-33"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>modifyMVar</span>
<a name="line-34"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>addMVarFinalizer</span>
<a name="line-35"></a> <span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-36"></a>
<a name="line-37"></a>
<a name="line-38"></a><span class='hs-comment'>--------------------------------------------------------------------------------</span>
<a name="line-39"></a><span class='hs-comment'>-- Imports</span>
<a name="line-40"></a><span class='hs-comment'>--------------------------------------------------------------------------------</span>
<a name="line-41"></a>
<a name="line-42"></a><span class='hs-comment'>-- from base:</span>
<a name="line-43"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Bool</span> <span class='hs-layout'>(</span> <span class='hs-conid'>Bool</span><span class='hs-layout'>(</span><span class='hs-conid'>False</span><span class='hs-layout'>,</span> <span class='hs-conid'>True</span><span class='hs-layout'>)</span> <span class='hs-layout'>)</span>
<a name="line-44"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Function</span> <span class='hs-layout'>(</span> <span class='hs-layout'>(</span><span class='hs-varop'>$</span><span class='hs-layout'>)</span> <span class='hs-layout'>)</span>
<a name="line-45"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Functor</span> <span class='hs-layout'>(</span> <span class='hs-varid'>fmap</span> <span class='hs-layout'>)</span>
<a name="line-46"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>IORef</span> <span class='hs-layout'>(</span> <span class='hs-varid'>newIORef</span><span class='hs-layout'>,</span> <span class='hs-varid'>readIORef</span><span class='hs-layout'>,</span> <span class='hs-varid'>writeIORef</span> <span class='hs-layout'>)</span>
<a name="line-47"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Maybe</span> <span class='hs-layout'>(</span> <span class='hs-conid'>Maybe</span> <span class='hs-layout'>)</span>
<a name="line-48"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Control</span><span class='hs-varop'>.</span><span class='hs-conid'>Monad</span> <span class='hs-layout'>(</span> <span class='hs-varid'>return</span><span class='hs-layout'>,</span> <span class='hs-varid'>when</span> <span class='hs-layout'>)</span>
<a name="line-49"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>System</span><span class='hs-varop'>.</span><span class='hs-conid'>IO</span> <span class='hs-layout'>(</span> <span class='hs-conid'>IO</span> <span class='hs-layout'>)</span>
<a name="line-50"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Control</span><span class='hs-varop'>.</span><span class='hs-conid'>Concurrent</span><span class='hs-varop'>.</span><span class='hs-conid'>MVar</span> <span class='hs-layout'>(</span> <span class='hs-conid'>MVar</span> <span class='hs-layout'>)</span>
<a name="line-51"></a><span class='hs-keyword'>import</span> <span class='hs-keyword'>qualified</span> <span class='hs-conid'>Control</span><span class='hs-varop'>.</span><span class='hs-conid'>Concurrent</span><span class='hs-varop'>.</span><span class='hs-conid'>MVar</span> <span class='hs-keyword'>as</span> <span class='hs-conid'>MVar</span>
<a name="line-52"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Control</span><span class='hs-varop'>.</span><span class='hs-conid'>Exception</span> <span class='hs-layout'>(</span> <span class='hs-varid'>onException</span>
<a name="line-53"></a><span class='hs-cpp'>#if MIN_VERSION_base(4,3,0)</span>
<a name="line-54"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>mask</span><span class='hs-layout'>,</span> <span class='hs-varid'>mask_</span>
<a name="line-55"></a><span class='hs-cpp'>#else</span>
<a name="line-56"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>block</span><span class='hs-layout'>,</span> <span class='hs-varid'>unblock</span>
<a name="line-57"></a><span class='hs-cpp'>#endif</span>
<a name="line-58"></a> <span class='hs-layout'>)</span>
<a name="line-59"></a>
<a name="line-60"></a><span class='hs-cpp'>#if __GLASGOW_HASKELL__ < 700</span>
<a name="line-61"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Control</span><span class='hs-varop'>.</span><span class='hs-conid'>Monad</span> <span class='hs-layout'>(</span> <span class='hs-layout'>(</span><span class='hs-varop'>>>=</span><span class='hs-layout'>)</span><span class='hs-layout'>,</span> <span class='hs-layout'>(</span><span class='hs-varop'>>></span><span class='hs-layout'>)</span><span class='hs-layout'>,</span> <span class='hs-varid'>fail</span> <span class='hs-layout'>)</span>
<a name="line-62"></a><span class='hs-cpp'>#endif</span>
<a name="line-63"></a>
<a name="line-64"></a><span class='hs-comment'>-- from base-unicode-symbols:</span>
<a name="line-65"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Function</span><span class='hs-varop'>.</span><span class='hs-conid'>Unicode</span> <span class='hs-layout'>(</span> <span class='hs-layout'>(</span><span class='hs-sel'>∘</span><span class='hs-layout'>)</span> <span class='hs-layout'>)</span>
<a name="line-66"></a>
<a name="line-67"></a><span class='hs-comment'>-- from transformers-base:</span>
<a name="line-68"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Control</span><span class='hs-varop'>.</span><span class='hs-conid'>Monad</span><span class='hs-varop'>.</span><span class='hs-conid'>Base</span> <span class='hs-layout'>(</span> <span class='hs-conid'>MonadBase</span><span class='hs-layout'>,</span> <span class='hs-varid'>liftBase</span> <span class='hs-layout'>)</span>
<a name="line-69"></a>
<a name="line-70"></a><span class='hs-comment'>-- from monad-control:</span>
<a name="line-71"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Control</span><span class='hs-varop'>.</span><span class='hs-conid'>Monad</span><span class='hs-varop'>.</span><span class='hs-conid'>Trans</span><span class='hs-varop'>.</span><span class='hs-conid'>Control</span> <span class='hs-layout'>(</span> <span class='hs-conid'>MonadBaseControl</span>
<a name="line-72"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>control</span>
<a name="line-73"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>liftBaseOp</span>
<a name="line-74"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>liftBaseDiscard</span>
<a name="line-75"></a> <span class='hs-layout'>)</span>
<a name="line-76"></a>
<a name="line-77"></a><span class='hs-cpp'>#include "inlinable.h"</span>
<a name="line-78"></a>
<a name="line-79"></a><span class='hs-comment'>--------------------------------------------------------------------------------</span>
<a name="line-80"></a><span class='hs-comment'>-- * MVars</span>
<a name="line-81"></a><span class='hs-comment'>--------------------------------------------------------------------------------</span>
<a name="line-82"></a>
<a name="line-83"></a><a name="newEmptyMVar"></a><span class='hs-comment'>-- | Generalized version of 'MVar.newEmptyMVar'.</span>
<a name="line-84"></a><span class='hs-definition'>newEmptyMVar</span> <span class='hs-sel'>∷</span> <span class='hs-conid'>MonadBase</span> <span class='hs-conid'>IO</span> <span class='hs-varid'>m</span> <span class='hs-sel'>⇒</span> <span class='hs-varid'>m</span> <span class='hs-layout'>(</span><span class='hs-conid'>MVar</span> <span class='hs-varid'>α</span><span class='hs-layout'>)</span>
<a name="line-85"></a><span class='hs-definition'>newEmptyMVar</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>liftBase</span> <span class='hs-conid'>MVar</span><span class='hs-varop'>.</span><span class='hs-varid'>newEmptyMVar</span>
<a name="line-86"></a><span class='hs-comment'>{-# INLINABLE newEmptyMVar #-}</span>
<a name="line-87"></a>
<a name="line-88"></a><a name="newMVar"></a><span class='hs-comment'>-- | Generalized version of 'MVar.newMVar'.</span>
<a name="line-89"></a><span class='hs-definition'>newMVar</span> <span class='hs-sel'>∷</span> <span class='hs-conid'>MonadBase</span> <span class='hs-conid'>IO</span> <span class='hs-varid'>m</span> <span class='hs-sel'>⇒</span> <span class='hs-varid'>α</span> <span class='hs-sel'>→</span> <span class='hs-varid'>m</span> <span class='hs-layout'>(</span><span class='hs-conid'>MVar</span> <span class='hs-varid'>α</span><span class='hs-layout'>)</span>
<a name="line-90"></a><span class='hs-definition'>newMVar</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>liftBase</span> <span class='hs-sel'>∘</span> <span class='hs-conid'>MVar</span><span class='hs-varop'>.</span><span class='hs-varid'>newMVar</span>
<a name="line-91"></a><span class='hs-comment'>{-# INLINABLE newMVar #-}</span>
<a name="line-92"></a>
<a name="line-93"></a><a name="takeMVar"></a><span class='hs-comment'>-- | Generalized version of 'MVar.takeMVar'.</span>
<a name="line-94"></a><span class='hs-definition'>takeMVar</span> <span class='hs-sel'>∷</span> <span class='hs-conid'>MonadBase</span> <span class='hs-conid'>IO</span> <span class='hs-varid'>m</span> <span class='hs-sel'>⇒</span> <span class='hs-conid'>MVar</span> <span class='hs-varid'>α</span> <span class='hs-sel'>→</span> <span class='hs-varid'>m</span> <span class='hs-varid'>α</span>
<a name="line-95"></a><span class='hs-definition'>takeMVar</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>liftBase</span> <span class='hs-sel'>∘</span> <span class='hs-conid'>MVar</span><span class='hs-varop'>.</span><span class='hs-varid'>takeMVar</span>
<a name="line-96"></a><span class='hs-comment'>{-# INLINABLE takeMVar #-}</span>
<a name="line-97"></a>
<a name="line-98"></a><a name="putMVar"></a><span class='hs-comment'>-- | Generalized version of 'MVar.putMVar'.</span>
<a name="line-99"></a><span class='hs-definition'>putMVar</span> <span class='hs-sel'>∷</span> <span class='hs-conid'>MonadBase</span> <span class='hs-conid'>IO</span> <span class='hs-varid'>m</span> <span class='hs-sel'>⇒</span> <span class='hs-conid'>MVar</span> <span class='hs-varid'>α</span> <span class='hs-sel'>→</span> <span class='hs-varid'>α</span> <span class='hs-sel'>→</span> <span class='hs-varid'>m</span> <span class='hs-conid'>()</span>
<a name="line-100"></a><span class='hs-definition'>putMVar</span> <span class='hs-varid'>mv</span> <span class='hs-varid'>x</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>liftBase</span> <span class='hs-varop'>$</span> <span class='hs-conid'>MVar</span><span class='hs-varop'>.</span><span class='hs-varid'>putMVar</span> <span class='hs-varid'>mv</span> <span class='hs-varid'>x</span>
<a name="line-101"></a><span class='hs-comment'>{-# INLINABLE putMVar #-}</span>
<a name="line-102"></a>
<a name="line-103"></a><a name="readMVar"></a><span class='hs-comment'>-- | Generalized version of 'MVar.readMVar'.</span>
<a name="line-104"></a><span class='hs-definition'>readMVar</span> <span class='hs-sel'>∷</span> <span class='hs-conid'>MonadBase</span> <span class='hs-conid'>IO</span> <span class='hs-varid'>m</span> <span class='hs-sel'>⇒</span> <span class='hs-conid'>MVar</span> <span class='hs-varid'>α</span> <span class='hs-sel'>→</span> <span class='hs-varid'>m</span> <span class='hs-varid'>α</span>
<a name="line-105"></a><span class='hs-definition'>readMVar</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>liftBase</span> <span class='hs-sel'>∘</span> <span class='hs-conid'>MVar</span><span class='hs-varop'>.</span><span class='hs-varid'>readMVar</span>
<a name="line-106"></a><span class='hs-comment'>{-# INLINABLE readMVar #-}</span>
<a name="line-107"></a>
<a name="line-108"></a><a name="swapMVar"></a><span class='hs-comment'>-- | Generalized version of 'MVar.swapMVar'.</span>
<a name="line-109"></a><span class='hs-definition'>swapMVar</span> <span class='hs-sel'>∷</span> <span class='hs-conid'>MonadBase</span> <span class='hs-conid'>IO</span> <span class='hs-varid'>m</span> <span class='hs-sel'>⇒</span> <span class='hs-conid'>MVar</span> <span class='hs-varid'>α</span> <span class='hs-sel'>→</span> <span class='hs-varid'>α</span> <span class='hs-sel'>→</span> <span class='hs-varid'>m</span> <span class='hs-varid'>α</span>
<a name="line-110"></a><span class='hs-definition'>swapMVar</span> <span class='hs-varid'>mv</span> <span class='hs-varid'>x</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>liftBase</span> <span class='hs-varop'>$</span> <span class='hs-conid'>MVar</span><span class='hs-varop'>.</span><span class='hs-varid'>swapMVar</span> <span class='hs-varid'>mv</span> <span class='hs-varid'>x</span>
<a name="line-111"></a><span class='hs-comment'>{-# INLINABLE swapMVar #-}</span>
<a name="line-112"></a>
<a name="line-113"></a><a name="tryTakeMVar"></a><span class='hs-comment'>-- | Generalized version of 'MVar.tryTakeMVar'.</span>
<a name="line-114"></a><span class='hs-definition'>tryTakeMVar</span> <span class='hs-sel'>∷</span> <span class='hs-conid'>MonadBase</span> <span class='hs-conid'>IO</span> <span class='hs-varid'>m</span> <span class='hs-sel'>⇒</span> <span class='hs-conid'>MVar</span> <span class='hs-varid'>α</span> <span class='hs-sel'>→</span> <span class='hs-varid'>m</span> <span class='hs-layout'>(</span><span class='hs-conid'>Maybe</span> <span class='hs-varid'>α</span><span class='hs-layout'>)</span>
<a name="line-115"></a><span class='hs-definition'>tryTakeMVar</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>liftBase</span> <span class='hs-sel'>∘</span> <span class='hs-conid'>MVar</span><span class='hs-varop'>.</span><span class='hs-varid'>tryTakeMVar</span>
<a name="line-116"></a><span class='hs-comment'>{-# INLINABLE tryTakeMVar #-}</span>
<a name="line-117"></a>
<a name="line-118"></a><a name="tryPutMVar"></a><span class='hs-comment'>-- | Generalized version of 'MVar.tryPutMVar'.</span>
<a name="line-119"></a><span class='hs-definition'>tryPutMVar</span> <span class='hs-sel'>∷</span> <span class='hs-conid'>MonadBase</span> <span class='hs-conid'>IO</span> <span class='hs-varid'>m</span> <span class='hs-sel'>⇒</span> <span class='hs-conid'>MVar</span> <span class='hs-varid'>α</span> <span class='hs-sel'>→</span> <span class='hs-varid'>α</span> <span class='hs-sel'>→</span> <span class='hs-varid'>m</span> <span class='hs-conid'>Bool</span>
<a name="line-120"></a><span class='hs-definition'>tryPutMVar</span> <span class='hs-varid'>mv</span> <span class='hs-varid'>x</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>liftBase</span> <span class='hs-varop'>$</span> <span class='hs-conid'>MVar</span><span class='hs-varop'>.</span><span class='hs-varid'>tryPutMVar</span> <span class='hs-varid'>mv</span> <span class='hs-varid'>x</span>
<a name="line-121"></a><span class='hs-comment'>{-# INLINABLE tryPutMVar #-}</span>
<a name="line-122"></a>
<a name="line-123"></a><a name="isEmptyMVar"></a><span class='hs-comment'>-- | Generalized version of 'MVar.isEmptyMVar'.</span>
<a name="line-124"></a><span class='hs-definition'>isEmptyMVar</span> <span class='hs-sel'>∷</span> <span class='hs-conid'>MonadBase</span> <span class='hs-conid'>IO</span> <span class='hs-varid'>m</span> <span class='hs-sel'>⇒</span> <span class='hs-conid'>MVar</span> <span class='hs-varid'>α</span> <span class='hs-sel'>→</span> <span class='hs-varid'>m</span> <span class='hs-conid'>Bool</span>
<a name="line-125"></a><span class='hs-definition'>isEmptyMVar</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>liftBase</span> <span class='hs-sel'>∘</span> <span class='hs-conid'>MVar</span><span class='hs-varop'>.</span><span class='hs-varid'>isEmptyMVar</span>
<a name="line-126"></a><span class='hs-comment'>{-# INLINABLE isEmptyMVar #-}</span>
<a name="line-127"></a>
<a name="line-128"></a><a name="withMVar"></a><span class='hs-comment'>-- | Generalized version of 'MVar.withMVar'.</span>
<a name="line-129"></a><span class='hs-definition'>withMVar</span> <span class='hs-sel'>∷</span> <span class='hs-conid'>MonadBaseControl</span> <span class='hs-conid'>IO</span> <span class='hs-varid'>m</span> <span class='hs-sel'>⇒</span> <span class='hs-conid'>MVar</span> <span class='hs-varid'>α</span> <span class='hs-sel'>→</span> <span class='hs-layout'>(</span><span class='hs-varid'>α</span> <span class='hs-sel'>→</span> <span class='hs-varid'>m</span> <span class='hs-varid'>β</span><span class='hs-layout'>)</span> <span class='hs-sel'>→</span> <span class='hs-varid'>m</span> <span class='hs-varid'>β</span>
<a name="line-130"></a><span class='hs-definition'>withMVar</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>liftBaseOp</span> <span class='hs-sel'>∘</span> <span class='hs-conid'>MVar</span><span class='hs-varop'>.</span><span class='hs-varid'>withMVar</span>
<a name="line-131"></a><span class='hs-comment'>{-# INLINABLE withMVar #-}</span>
<a name="line-132"></a>
<a name="line-133"></a><a name="modifyMVar_"></a><span class='hs-comment'>-- | Generalized version of 'MVar.modifyMVar_'.</span>
<a name="line-134"></a><span class='hs-definition'>modifyMVar_</span> <span class='hs-sel'>∷</span> <span class='hs-layout'>(</span><span class='hs-conid'>MonadBaseControl</span> <span class='hs-conid'>IO</span> <span class='hs-varid'>m</span><span class='hs-layout'>,</span> <span class='hs-conid'>MonadBase</span> <span class='hs-conid'>IO</span> <span class='hs-varid'>m</span><span class='hs-layout'>)</span> <span class='hs-sel'>⇒</span> <span class='hs-conid'>MVar</span> <span class='hs-varid'>α</span> <span class='hs-sel'>→</span> <span class='hs-layout'>(</span><span class='hs-varid'>α</span> <span class='hs-sel'>→</span> <span class='hs-varid'>m</span> <span class='hs-varid'>α</span><span class='hs-layout'>)</span> <span class='hs-sel'>→</span> <span class='hs-varid'>m</span> <span class='hs-conid'>()</span>
<a name="line-135"></a><span class='hs-definition'>modifyMVar_</span> <span class='hs-varid'>mv</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>modifyMVar</span> <span class='hs-varid'>mv</span> <span class='hs-sel'>∘</span> <span class='hs-layout'>(</span><span class='hs-varid'>fmap</span> <span class='hs-layout'>(</span><span class='hs-layout'>,</span> <span class='hs-conid'>()</span><span class='hs-layout'>)</span> <span class='hs-sel'>∘</span><span class='hs-layout'>)</span>
<a name="line-136"></a><span class='hs-comment'>{-# INLINABLE modifyMVar_ #-}</span>
<a name="line-137"></a>
<a name="line-138"></a><a name="modifyMVar"></a><span class='hs-comment'>-- | Generalized version of 'MVar.modifyMVar'.</span>
<a name="line-139"></a><span class='hs-definition'>modifyMVar</span> <span class='hs-sel'>∷</span> <span class='hs-layout'>(</span><span class='hs-conid'>MonadBaseControl</span> <span class='hs-conid'>IO</span> <span class='hs-varid'>m</span><span class='hs-layout'>,</span> <span class='hs-conid'>MonadBase</span> <span class='hs-conid'>IO</span> <span class='hs-varid'>m</span><span class='hs-layout'>)</span> <span class='hs-sel'>⇒</span> <span class='hs-conid'>MVar</span> <span class='hs-varid'>α</span> <span class='hs-sel'>→</span> <span class='hs-layout'>(</span><span class='hs-varid'>α</span> <span class='hs-sel'>→</span> <span class='hs-varid'>m</span> <span class='hs-layout'>(</span><span class='hs-varid'>α</span><span class='hs-layout'>,</span> <span class='hs-varid'>β</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span> <span class='hs-sel'>→</span> <span class='hs-varid'>m</span> <span class='hs-varid'>β</span>
<a name="line-140"></a>
<a name="line-141"></a><span class='hs-cpp'>#if MIN_VERSION_base(4,3,0)</span>
<a name="line-142"></a><span class='hs-definition'>modifyMVar</span> <span class='hs-varid'>mv</span> <span class='hs-varid'>f</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>control</span> <span class='hs-varop'>$</span> <span class='hs-keyglyph'>\</span><span class='hs-varid'>runInIO</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>mask</span> <span class='hs-varop'>$</span> <span class='hs-keyglyph'>\</span><span class='hs-varid'>restore</span> <span class='hs-sel'>→</span> <span class='hs-keyword'>do</span>
<a name="line-143"></a> <span class='hs-varid'>aborted</span> <span class='hs-sel'>←</span> <span class='hs-varid'>newIORef</span> <span class='hs-conid'>True</span>
<a name="line-144"></a> <span class='hs-keyword'>let</span> <span class='hs-varid'>f'</span> <span class='hs-varid'>x</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>do</span>
<a name="line-145"></a> <span class='hs-layout'>(</span><span class='hs-varid'>x'</span><span class='hs-layout'>,</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-sel'>←</span> <span class='hs-varid'>f</span> <span class='hs-varid'>x</span>
<a name="line-146"></a> <span class='hs-varid'>liftBase</span> <span class='hs-varop'>$</span> <span class='hs-varid'>mask_</span> <span class='hs-varop'>$</span> <span class='hs-keyword'>do</span>
<a name="line-147"></a> <span class='hs-varid'>writeIORef</span> <span class='hs-varid'>aborted</span> <span class='hs-conid'>False</span>
<a name="line-148"></a> <span class='hs-conid'>MVar</span><span class='hs-varop'>.</span><span class='hs-varid'>putMVar</span> <span class='hs-varid'>mv</span> <span class='hs-varid'>x'</span>
<a name="line-149"></a> <span class='hs-varid'>return</span> <span class='hs-varid'>a</span>
<a name="line-150"></a> <span class='hs-varid'>x</span> <span class='hs-sel'>←</span> <span class='hs-conid'>MVar</span><span class='hs-varop'>.</span><span class='hs-varid'>takeMVar</span> <span class='hs-varid'>mv</span>
<a name="line-151"></a> <span class='hs-varid'>stM</span> <span class='hs-sel'>←</span> <span class='hs-varid'>restore</span> <span class='hs-layout'>(</span><span class='hs-varid'>runInIO</span> <span class='hs-layout'>(</span><span class='hs-varid'>f'</span> <span class='hs-varid'>x</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span> <span class='hs-varop'>`onException`</span> <span class='hs-conid'>MVar</span><span class='hs-varop'>.</span><span class='hs-varid'>putMVar</span> <span class='hs-varid'>mv</span> <span class='hs-varid'>x</span>
<a name="line-152"></a> <span class='hs-varid'>abort</span> <span class='hs-sel'>←</span> <span class='hs-varid'>readIORef</span> <span class='hs-varid'>aborted</span>
<a name="line-153"></a> <span class='hs-varid'>when</span> <span class='hs-varid'>abort</span> <span class='hs-varop'>$</span> <span class='hs-conid'>MVar</span><span class='hs-varop'>.</span><span class='hs-varid'>putMVar</span> <span class='hs-varid'>mv</span> <span class='hs-varid'>x</span>
<a name="line-154"></a> <span class='hs-varid'>return</span> <span class='hs-varid'>stM</span>
<a name="line-155"></a><span class='hs-cpp'>#else</span>
<a name="line-156"></a><span class='hs-definition'>modifyMVar</span> <span class='hs-varid'>mv</span> <span class='hs-varid'>f</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>control</span> <span class='hs-varop'>$</span> <span class='hs-keyglyph'>\</span><span class='hs-varid'>runInIO</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>block</span> <span class='hs-varop'>$</span> <span class='hs-keyword'>do</span>
<a name="line-157"></a> <span class='hs-varid'>aborted</span> <span class='hs-sel'>←</span> <span class='hs-varid'>newIORef</span> <span class='hs-conid'>True</span>
<a name="line-158"></a> <span class='hs-keyword'>let</span> <span class='hs-varid'>f'</span> <span class='hs-varid'>x</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>do</span>
<a name="line-159"></a> <span class='hs-layout'>(</span><span class='hs-varid'>x'</span><span class='hs-layout'>,</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-sel'>←</span> <span class='hs-varid'>f</span> <span class='hs-varid'>x</span>
<a name="line-160"></a> <span class='hs-varid'>liftBase</span> <span class='hs-varop'>$</span> <span class='hs-varid'>block</span> <span class='hs-varop'>$</span> <span class='hs-keyword'>do</span>
<a name="line-161"></a> <span class='hs-varid'>writeIORef</span> <span class='hs-varid'>aborted</span> <span class='hs-conid'>False</span>
<a name="line-162"></a> <span class='hs-conid'>MVar</span><span class='hs-varop'>.</span><span class='hs-varid'>putMVar</span> <span class='hs-varid'>mv</span> <span class='hs-varid'>x'</span>
<a name="line-163"></a> <span class='hs-varid'>return</span> <span class='hs-varid'>a</span>
<a name="line-164"></a> <span class='hs-varid'>x</span> <span class='hs-sel'>←</span> <span class='hs-conid'>MVar</span><span class='hs-varop'>.</span><span class='hs-varid'>takeMVar</span> <span class='hs-varid'>mv</span>
<a name="line-165"></a> <span class='hs-varid'>stM</span> <span class='hs-sel'>←</span> <span class='hs-varid'>unblock</span> <span class='hs-layout'>(</span><span class='hs-varid'>runInIO</span> <span class='hs-layout'>(</span><span class='hs-varid'>f'</span> <span class='hs-varid'>x</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span> <span class='hs-varop'>`onException`</span> <span class='hs-conid'>MVar</span><span class='hs-varop'>.</span><span class='hs-varid'>putMVar</span> <span class='hs-varid'>mv</span> <span class='hs-varid'>x</span>
<a name="line-166"></a> <span class='hs-varid'>abort</span> <span class='hs-sel'>←</span> <span class='hs-varid'>readIORef</span> <span class='hs-varid'>aborted</span>
<a name="line-167"></a> <span class='hs-varid'>when</span> <span class='hs-varid'>abort</span> <span class='hs-varop'>$</span> <span class='hs-conid'>MVar</span><span class='hs-varop'>.</span><span class='hs-varid'>putMVar</span> <span class='hs-varid'>mv</span> <span class='hs-varid'>x</span>
<a name="line-168"></a> <span class='hs-varid'>return</span> <span class='hs-varid'>stM</span>
<a name="line-169"></a><span class='hs-cpp'>#endif</span>
<a name="line-170"></a><span class='hs-comment'>{-# INLINABLE modifyMVar #-}</span>
<a name="line-171"></a>
<a name="line-172"></a><a name="addMVarFinalizer"></a><span class='hs-comment'>-- | Generalized version of 'MVar.addMVarFinalizer'.</span>
<a name="line-173"></a><span class='hs-comment'>--</span>
<a name="line-174"></a><span class='hs-comment'>-- Note any monadic side effects in @m@ of the \"finalizer\" computation are</span>
<a name="line-175"></a><span class='hs-comment'>-- discarded.</span>
<a name="line-176"></a><span class='hs-definition'>addMVarFinalizer</span> <span class='hs-sel'>∷</span> <span class='hs-conid'>MonadBaseControl</span> <span class='hs-conid'>IO</span> <span class='hs-varid'>m</span> <span class='hs-sel'>⇒</span> <span class='hs-conid'>MVar</span> <span class='hs-varid'>α</span> <span class='hs-sel'>→</span> <span class='hs-varid'>m</span> <span class='hs-conid'>()</span> <span class='hs-sel'>→</span> <span class='hs-varid'>m</span> <span class='hs-conid'>()</span>
<a name="line-177"></a><span class='hs-definition'>addMVarFinalizer</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>liftBaseDiscard</span> <span class='hs-sel'>∘</span> <span class='hs-conid'>MVar</span><span class='hs-varop'>.</span><span class='hs-varid'>addMVarFinalizer</span>
<a name="line-178"></a><span class='hs-comment'>{-# INLINABLE addMVarFinalizer #-}</span>
</pre></body>
</html>
