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<pre><a name="line-1"></a><span class='hs-comment'>{-# LANGUAGE CPP #-}</span>
<a name="line-2"></a><span class='hs-comment'>{-# LANGUAGE Rank2Types #-}</span>
<a name="line-3"></a><span class='hs-comment'>{-# LANGUAGE FlexibleContexts #-}</span>
<a name="line-4"></a><span class='hs-comment'>{-# LANGUAGE UndecidableInstances #-}</span>
<a name="line-5"></a><span class='hs-cpp'>#if __GLASGOW_HASKELL__ >= 711</span>
<a name="line-6"></a><span class='hs-comment'>{-# OPTIONS_GHC -fno-warn-redundant-constraints #-}</span>
<a name="line-7"></a><span class='hs-cpp'>#endif</span>
<a name="line-8"></a>
<a name="line-9"></a><span class='hs-comment'>-----------------------------------------------------------------------------</span>
<a name="line-10"></a><span class='hs-comment'>-- |</span>
<a name="line-11"></a><span class='hs-comment'>-- Module : Control.Lens.Internal.Fold</span>
<a name="line-12"></a><span class='hs-comment'>-- Copyright : (C) 2012-2016 Edward Kmett</span>
<a name="line-13"></a><span class='hs-comment'>-- License : BSD-style (see the file LICENSE)</span>
<a name="line-14"></a><span class='hs-comment'>-- Maintainer : Edward Kmett <ekmett@gmail.com></span>
<a name="line-15"></a><span class='hs-comment'>-- Stability : experimental</span>
<a name="line-16"></a><span class='hs-comment'>-- Portability : non-portable</span>
<a name="line-17"></a><span class='hs-comment'>--</span>
<a name="line-18"></a><span class='hs-comment'>----------------------------------------------------------------------------</span>
<a name="line-19"></a><span class='hs-keyword'>module</span> <span class='hs-conid'>Control</span><span class='hs-varop'>.</span><span class='hs-conid'>Lens</span><span class='hs-varop'>.</span><span class='hs-conid'>Internal</span><span class='hs-varop'>.</span><span class='hs-conid'>Fold</span>
<a name="line-20"></a> <span class='hs-layout'>(</span>
<a name="line-21"></a> <span class='hs-comment'>-- * Monoids for folding</span>
<a name="line-22"></a> <span class='hs-conid'>Folding</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span>
<a name="line-23"></a> <span class='hs-layout'>,</span> <span class='hs-conid'>Traversed</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span>
<a name="line-24"></a> <span class='hs-layout'>,</span> <span class='hs-conid'>Sequenced</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span>
<a name="line-25"></a> <span class='hs-layout'>,</span> <span class='hs-conid'>Max</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span><span class='hs-layout'>,</span> <span class='hs-varid'>getMax</span>
<a name="line-26"></a> <span class='hs-layout'>,</span> <span class='hs-conid'>Min</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span><span class='hs-layout'>,</span> <span class='hs-varid'>getMin</span>
<a name="line-27"></a> <span class='hs-layout'>,</span> <span class='hs-conid'>Leftmost</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span><span class='hs-layout'>,</span> <span class='hs-varid'>getLeftmost</span>
<a name="line-28"></a> <span class='hs-layout'>,</span> <span class='hs-conid'>Rightmost</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span><span class='hs-layout'>,</span> <span class='hs-varid'>getRightmost</span>
<a name="line-29"></a> <span class='hs-layout'>,</span> <span class='hs-conid'>ReifiedMonoid</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span>
<a name="line-30"></a> <span class='hs-comment'>-- * Semigroups for folding</span>
<a name="line-31"></a> <span class='hs-layout'>,</span> <span class='hs-conid'>NonEmptyDList</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span>
<a name="line-32"></a> <span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-33"></a>
<a name="line-34"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Control</span><span class='hs-varop'>.</span><span class='hs-conid'>Applicative</span>
<a name="line-35"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Control</span><span class='hs-varop'>.</span><span class='hs-conid'>Lens</span><span class='hs-varop'>.</span><span class='hs-conid'>Internal</span><span class='hs-varop'>.</span><span class='hs-conid'>Getter</span>
<a name="line-36"></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-varop'>.</span><span class='hs-conid'>Bind</span>
<a name="line-37"></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-varop'>.</span><span class='hs-conid'>Contravariant</span>
<a name="line-38"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Maybe</span>
<a name="line-39"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Semigroup</span> <span class='hs-varid'>hiding</span> <span class='hs-layout'>(</span><span class='hs-conid'>Min</span><span class='hs-layout'>,</span> <span class='hs-varid'>getMin</span><span class='hs-layout'>,</span> <span class='hs-conid'>Max</span><span class='hs-layout'>,</span> <span class='hs-varid'>getMax</span><span class='hs-layout'>)</span>
<a name="line-40"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Reflection</span>
<a name="line-41"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Prelude</span>
<a name="line-42"></a>
<a name="line-43"></a><span class='hs-keyword'>import</span> <span class='hs-keyword'>qualified</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>List</span><span class='hs-varop'>.</span><span class='hs-conid'>NonEmpty</span> <span class='hs-keyword'>as</span> <span class='hs-conid'>NonEmpty</span>
<a name="line-44"></a>
<a name="line-45"></a><span class='hs-cpp'>#ifdef HLINT</span>
<a name="line-46"></a><span class='hs-comment'>{-# ANN module "HLint: ignore Avoid lambda" #-}</span>
<a name="line-47"></a><span class='hs-cpp'>#endif</span>
<a name="line-48"></a>
<a name="line-49"></a><span class='hs-comment'>------------------------------------------------------------------------------</span>
<a name="line-50"></a><span class='hs-comment'>-- Folding</span>
<a name="line-51"></a><span class='hs-comment'>------------------------------------------------------------------------------</span>
<a name="line-52"></a>
<a name="line-53"></a><a name="Folding"></a><span class='hs-comment'>-- | A 'Monoid' for a 'Contravariant' 'Applicative'.</span>
<a name="line-54"></a><a name="Folding"></a><span class='hs-keyword'>newtype</span> <span class='hs-conid'>Folding</span> <span class='hs-varid'>f</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Folding</span> <span class='hs-layout'>{</span> <span class='hs-varid'>getFolding</span> <span class='hs-keyglyph'>::</span> <span class='hs-varid'>f</span> <span class='hs-varid'>a</span> <span class='hs-layout'>}</span>
<a name="line-55"></a>
<a name="line-56"></a><a name="instance%20Semigroup%20(Folding%20f%20a)"></a><span class='hs-keyword'>instance</span> <span class='hs-layout'>(</span><span class='hs-conid'>Contravariant</span> <span class='hs-varid'>f</span><span class='hs-layout'>,</span> <span class='hs-conid'>Apply</span> <span class='hs-varid'>f</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=></span> <span class='hs-conid'>Semigroup</span> <span class='hs-layout'>(</span><span class='hs-conid'>Folding</span> <span class='hs-varid'>f</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-57"></a> <span class='hs-conid'>Folding</span> <span class='hs-varid'>fr</span> <span class='hs-varop'><></span> <span class='hs-conid'>Folding</span> <span class='hs-varid'>fs</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Folding</span> <span class='hs-layout'>(</span><span class='hs-varid'>fr</span> <span class='hs-varop'>.></span> <span class='hs-varid'>fs</span><span class='hs-layout'>)</span>
<a name="line-58"></a> <span class='hs-comment'>{-# INLINE (<>) #-}</span>
<a name="line-59"></a>
<a name="line-60"></a><a name="instance%20Monoid%20(Folding%20f%20a)"></a><span class='hs-keyword'>instance</span> <span class='hs-layout'>(</span><span class='hs-conid'>Contravariant</span> <span class='hs-varid'>f</span><span class='hs-layout'>,</span> <span class='hs-conid'>Applicative</span> <span class='hs-varid'>f</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=></span> <span class='hs-conid'>Monoid</span> <span class='hs-layout'>(</span><span class='hs-conid'>Folding</span> <span class='hs-varid'>f</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-61"></a> <span class='hs-varid'>mempty</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Folding</span> <span class='hs-varid'>noEffect</span>
<a name="line-62"></a> <span class='hs-comment'>{-# INLINE mempty #-}</span>
<a name="line-63"></a> <span class='hs-conid'>Folding</span> <span class='hs-varid'>fr</span> <span class='hs-varop'>`mappend`</span> <span class='hs-conid'>Folding</span> <span class='hs-varid'>fs</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Folding</span> <span class='hs-layout'>(</span><span class='hs-varid'>fr</span> <span class='hs-varop'>*></span> <span class='hs-varid'>fs</span><span class='hs-layout'>)</span>
<a name="line-64"></a> <span class='hs-comment'>{-# INLINE mappend #-}</span>
<a name="line-65"></a>
<a name="line-66"></a><span class='hs-comment'>------------------------------------------------------------------------------</span>
<a name="line-67"></a><span class='hs-comment'>-- Traversed</span>
<a name="line-68"></a><span class='hs-comment'>------------------------------------------------------------------------------</span>
<a name="line-69"></a>
<a name="line-70"></a><a name="Traversed"></a><span class='hs-comment'>-- | Used internally by 'Control.Lens.Traversal.traverseOf_' and the like.</span>
<a name="line-71"></a><a name="Traversed"></a><span class='hs-comment'>--</span>
<a name="line-72"></a><a name="Traversed"></a><span class='hs-comment'>-- The argument 'a' of the result should not be used!</span>
<a name="line-73"></a><a name="Traversed"></a><span class='hs-keyword'>newtype</span> <span class='hs-conid'>Traversed</span> <span class='hs-varid'>a</span> <span class='hs-varid'>f</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Traversed</span> <span class='hs-layout'>{</span> <span class='hs-varid'>getTraversed</span> <span class='hs-keyglyph'>::</span> <span class='hs-varid'>f</span> <span class='hs-varid'>a</span> <span class='hs-layout'>}</span>
<a name="line-74"></a>
<a name="line-75"></a><a name="instance%20Semigroup%20(Traversed%20a%20f)"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>Apply</span> <span class='hs-varid'>f</span> <span class='hs-keyglyph'>=></span> <span class='hs-conid'>Semigroup</span> <span class='hs-layout'>(</span><span class='hs-conid'>Traversed</span> <span class='hs-varid'>a</span> <span class='hs-varid'>f</span><span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-76"></a> <span class='hs-conid'>Traversed</span> <span class='hs-varid'>ma</span> <span class='hs-varop'><></span> <span class='hs-conid'>Traversed</span> <span class='hs-varid'>mb</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Traversed</span> <span class='hs-layout'>(</span><span class='hs-varid'>ma</span> <span class='hs-varop'>.></span> <span class='hs-varid'>mb</span><span class='hs-layout'>)</span>
<a name="line-77"></a> <span class='hs-comment'>{-# INLINE (<>) #-}</span>
<a name="line-78"></a>
<a name="line-79"></a><a name="instance%20Monoid%20(Traversed%20a%20f)"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>Applicative</span> <span class='hs-varid'>f</span> <span class='hs-keyglyph'>=></span> <span class='hs-conid'>Monoid</span> <span class='hs-layout'>(</span><span class='hs-conid'>Traversed</span> <span class='hs-varid'>a</span> <span class='hs-varid'>f</span><span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-80"></a> <span class='hs-varid'>mempty</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Traversed</span> <span class='hs-layout'>(</span><span class='hs-varid'>pure</span> <span class='hs-layout'>(</span><span class='hs-varid'>error</span> <span class='hs-str'>"Traversed: value used"</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span>
<a name="line-81"></a> <span class='hs-comment'>{-# INLINE mempty #-}</span>
<a name="line-82"></a> <span class='hs-conid'>Traversed</span> <span class='hs-varid'>ma</span> <span class='hs-varop'>`mappend`</span> <span class='hs-conid'>Traversed</span> <span class='hs-varid'>mb</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Traversed</span> <span class='hs-layout'>(</span><span class='hs-varid'>ma</span> <span class='hs-varop'>*></span> <span class='hs-varid'>mb</span><span class='hs-layout'>)</span>
<a name="line-83"></a> <span class='hs-comment'>{-# INLINE mappend #-}</span>
<a name="line-84"></a>
<a name="line-85"></a><span class='hs-comment'>------------------------------------------------------------------------------</span>
<a name="line-86"></a><span class='hs-comment'>-- Sequenced</span>
<a name="line-87"></a><span class='hs-comment'>------------------------------------------------------------------------------</span>
<a name="line-88"></a>
<a name="line-89"></a><a name="Sequenced"></a><span class='hs-comment'>-- | Used internally by 'Control.Lens.Traversal.mapM_' and the like.</span>
<a name="line-90"></a><a name="Sequenced"></a><span class='hs-comment'>--</span>
<a name="line-91"></a><a name="Sequenced"></a><span class='hs-comment'>-- The argument 'a' of the result should not be used!</span>
<a name="line-92"></a><a name="Sequenced"></a><span class='hs-keyword'>newtype</span> <span class='hs-conid'>Sequenced</span> <span class='hs-varid'>a</span> <span class='hs-varid'>m</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Sequenced</span> <span class='hs-layout'>{</span> <span class='hs-varid'>getSequenced</span> <span class='hs-keyglyph'>::</span> <span class='hs-varid'>m</span> <span class='hs-varid'>a</span> <span class='hs-layout'>}</span>
<a name="line-93"></a>
<a name="line-94"></a><a name="instance%20Semigroup%20(Sequenced%20a%20m)"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>Apply</span> <span class='hs-varid'>m</span> <span class='hs-keyglyph'>=></span> <span class='hs-conid'>Semigroup</span> <span class='hs-layout'>(</span><span class='hs-conid'>Sequenced</span> <span class='hs-varid'>a</span> <span class='hs-varid'>m</span><span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-95"></a> <span class='hs-conid'>Sequenced</span> <span class='hs-varid'>ma</span> <span class='hs-varop'><></span> <span class='hs-conid'>Sequenced</span> <span class='hs-varid'>mb</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Sequenced</span> <span class='hs-layout'>(</span><span class='hs-varid'>ma</span> <span class='hs-varop'>.></span> <span class='hs-varid'>mb</span><span class='hs-layout'>)</span>
<a name="line-96"></a> <span class='hs-comment'>{-# INLINE (<>) #-}</span>
<a name="line-97"></a>
<a name="line-98"></a><a name="instance%20Monoid%20(Sequenced%20a%20m)"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>Monad</span> <span class='hs-varid'>m</span> <span class='hs-keyglyph'>=></span> <span class='hs-conid'>Monoid</span> <span class='hs-layout'>(</span><span class='hs-conid'>Sequenced</span> <span class='hs-varid'>a</span> <span class='hs-varid'>m</span><span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-99"></a> <span class='hs-varid'>mempty</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Sequenced</span> <span class='hs-layout'>(</span><span class='hs-varid'>return</span> <span class='hs-layout'>(</span><span class='hs-varid'>error</span> <span class='hs-str'>"Sequenced: value used"</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span>
<a name="line-100"></a> <span class='hs-comment'>{-# INLINE mempty #-}</span>
<a name="line-101"></a> <span class='hs-conid'>Sequenced</span> <span class='hs-varid'>ma</span> <span class='hs-varop'>`mappend`</span> <span class='hs-conid'>Sequenced</span> <span class='hs-varid'>mb</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Sequenced</span> <span class='hs-layout'>(</span><span class='hs-varid'>ma</span> <span class='hs-varop'>>></span> <span class='hs-varid'>mb</span><span class='hs-layout'>)</span>
<a name="line-102"></a> <span class='hs-comment'>{-# INLINE mappend #-}</span>
<a name="line-103"></a>
<a name="line-104"></a><span class='hs-comment'>------------------------------------------------------------------------------</span>
<a name="line-105"></a><span class='hs-comment'>-- Min</span>
<a name="line-106"></a><span class='hs-comment'>------------------------------------------------------------------------------</span>
<a name="line-107"></a>
<a name="line-108"></a><a name="Min"></a><span class='hs-comment'>-- | Used for 'Control.Lens.Fold.minimumOf'.</span>
<a name="line-109"></a><a name="Min"></a><span class='hs-keyword'>data</span> <span class='hs-conid'>Min</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>NoMin</span> <span class='hs-keyglyph'>|</span> <span class='hs-conid'>Min</span> <span class='hs-varid'>a</span>
<a name="line-110"></a>
<a name="line-111"></a><a name="instance%20Semigroup%20(Min%20a)"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>Ord</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>=></span> <span class='hs-conid'>Semigroup</span> <span class='hs-layout'>(</span><span class='hs-conid'>Min</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-112"></a> <span class='hs-conid'>NoMin</span> <span class='hs-varop'><></span> <span class='hs-varid'>m</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>m</span>
<a name="line-113"></a> <span class='hs-varid'>m</span> <span class='hs-varop'><></span> <span class='hs-conid'>NoMin</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>m</span>
<a name="line-114"></a> <span class='hs-conid'>Min</span> <span class='hs-varid'>a</span> <span class='hs-varop'><></span> <span class='hs-conid'>Min</span> <span class='hs-varid'>b</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Min</span> <span class='hs-layout'>(</span><span class='hs-varid'>min</span> <span class='hs-varid'>a</span> <span class='hs-varid'>b</span><span class='hs-layout'>)</span>
<a name="line-115"></a> <span class='hs-comment'>{-# INLINE (<>) #-}</span>
<a name="line-116"></a>
<a name="line-117"></a><a name="instance%20Monoid%20(Min%20a)"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>Ord</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>=></span> <span class='hs-conid'>Monoid</span> <span class='hs-layout'>(</span><span class='hs-conid'>Min</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-118"></a> <span class='hs-varid'>mempty</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>NoMin</span>
<a name="line-119"></a> <span class='hs-comment'>{-# INLINE mempty #-}</span>
<a name="line-120"></a> <span class='hs-varid'>mappend</span> <span class='hs-conid'>NoMin</span> <span class='hs-varid'>m</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>m</span>
<a name="line-121"></a> <span class='hs-varid'>mappend</span> <span class='hs-varid'>m</span> <span class='hs-conid'>NoMin</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>m</span>
<a name="line-122"></a> <span class='hs-varid'>mappend</span> <span class='hs-layout'>(</span><span class='hs-conid'>Min</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-layout'>(</span><span class='hs-conid'>Min</span> <span class='hs-varid'>b</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Min</span> <span class='hs-layout'>(</span><span class='hs-varid'>min</span> <span class='hs-varid'>a</span> <span class='hs-varid'>b</span><span class='hs-layout'>)</span>
<a name="line-123"></a> <span class='hs-comment'>{-# INLINE mappend #-}</span>
<a name="line-124"></a>
<a name="line-125"></a><a name="getMin"></a><span class='hs-comment'>-- | Obtain the minimum.</span>
<a name="line-126"></a><span class='hs-definition'>getMin</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Min</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Maybe</span> <span class='hs-varid'>a</span>
<a name="line-127"></a><span class='hs-definition'>getMin</span> <span class='hs-conid'>NoMin</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Nothing</span>
<a name="line-128"></a><span class='hs-definition'>getMin</span> <span class='hs-layout'>(</span><span class='hs-conid'>Min</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Just</span> <span class='hs-varid'>a</span>
<a name="line-129"></a><span class='hs-comment'>{-# INLINE getMin #-}</span>
<a name="line-130"></a>
<a name="line-131"></a><span class='hs-comment'>------------------------------------------------------------------------------</span>
<a name="line-132"></a><span class='hs-comment'>-- Max</span>
<a name="line-133"></a><span class='hs-comment'>------------------------------------------------------------------------------</span>
<a name="line-134"></a>
<a name="line-135"></a><a name="Max"></a><span class='hs-comment'>-- | Used for 'Control.Lens.Fold.maximumOf'.</span>
<a name="line-136"></a><a name="Max"></a><span class='hs-keyword'>data</span> <span class='hs-conid'>Max</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>NoMax</span> <span class='hs-keyglyph'>|</span> <span class='hs-conid'>Max</span> <span class='hs-varid'>a</span>
<a name="line-137"></a>
<a name="line-138"></a><a name="instance%20Semigroup%20(Max%20a)"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>Ord</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>=></span> <span class='hs-conid'>Semigroup</span> <span class='hs-layout'>(</span><span class='hs-conid'>Max</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-139"></a> <span class='hs-conid'>NoMax</span> <span class='hs-varop'><></span> <span class='hs-varid'>m</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>m</span>
<a name="line-140"></a> <span class='hs-varid'>m</span> <span class='hs-varop'><></span> <span class='hs-conid'>NoMax</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>m</span>
<a name="line-141"></a> <span class='hs-conid'>Max</span> <span class='hs-varid'>a</span> <span class='hs-varop'><></span> <span class='hs-conid'>Max</span> <span class='hs-varid'>b</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Max</span> <span class='hs-layout'>(</span><span class='hs-varid'>max</span> <span class='hs-varid'>a</span> <span class='hs-varid'>b</span><span class='hs-layout'>)</span>
<a name="line-142"></a> <span class='hs-comment'>{-# INLINE (<>) #-}</span>
<a name="line-143"></a>
<a name="line-144"></a><a name="instance%20Monoid%20(Max%20a)"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>Ord</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>=></span> <span class='hs-conid'>Monoid</span> <span class='hs-layout'>(</span><span class='hs-conid'>Max</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-145"></a> <span class='hs-varid'>mempty</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>NoMax</span>
<a name="line-146"></a> <span class='hs-comment'>{-# INLINE mempty #-}</span>
<a name="line-147"></a> <span class='hs-varid'>mappend</span> <span class='hs-conid'>NoMax</span> <span class='hs-varid'>m</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>m</span>
<a name="line-148"></a> <span class='hs-varid'>mappend</span> <span class='hs-varid'>m</span> <span class='hs-conid'>NoMax</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>m</span>
<a name="line-149"></a> <span class='hs-varid'>mappend</span> <span class='hs-layout'>(</span><span class='hs-conid'>Max</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-layout'>(</span><span class='hs-conid'>Max</span> <span class='hs-varid'>b</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Max</span> <span class='hs-layout'>(</span><span class='hs-varid'>max</span> <span class='hs-varid'>a</span> <span class='hs-varid'>b</span><span class='hs-layout'>)</span>
<a name="line-150"></a> <span class='hs-comment'>{-# INLINE mappend #-}</span>
<a name="line-151"></a>
<a name="line-152"></a><a name="getMax"></a><span class='hs-comment'>-- | Obtain the maximum.</span>
<a name="line-153"></a><span class='hs-definition'>getMax</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Max</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Maybe</span> <span class='hs-varid'>a</span>
<a name="line-154"></a><span class='hs-definition'>getMax</span> <span class='hs-conid'>NoMax</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Nothing</span>
<a name="line-155"></a><span class='hs-definition'>getMax</span> <span class='hs-layout'>(</span><span class='hs-conid'>Max</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Just</span> <span class='hs-varid'>a</span>
<a name="line-156"></a><span class='hs-comment'>{-# INLINE getMax #-}</span>
<a name="line-157"></a>
<a name="line-158"></a><span class='hs-comment'>------------------------------------------------------------------------------</span>
<a name="line-159"></a><span class='hs-comment'>-- NonEmptyDList</span>
<a name="line-160"></a><span class='hs-comment'>------------------------------------------------------------------------------</span>
<a name="line-161"></a>
<a name="line-162"></a><a name="NonEmptyDList"></a><span class='hs-keyword'>newtype</span> <span class='hs-conid'>NonEmptyDList</span> <span class='hs-varid'>a</span>
<a name="line-163"></a> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>NonEmptyDList</span> <span class='hs-layout'>{</span> <span class='hs-varid'>getNonEmptyDList</span> <span class='hs-keyglyph'>::</span> <span class='hs-keyglyph'>[</span><span class='hs-varid'>a</span><span class='hs-keyglyph'>]</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>NonEmpty</span><span class='hs-varop'>.</span><span class='hs-conid'>NonEmpty</span> <span class='hs-varid'>a</span> <span class='hs-layout'>}</span>
<a name="line-164"></a>
<a name="line-165"></a><a name="instance%20Semigroup%20(NonEmptyDList%20a)"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>Semigroup</span> <span class='hs-layout'>(</span><span class='hs-conid'>NonEmptyDList</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-166"></a> <span class='hs-conid'>NonEmptyDList</span> <span class='hs-varid'>f</span> <span class='hs-varop'><></span> <span class='hs-conid'>NonEmptyDList</span> <span class='hs-varid'>g</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>NonEmptyDList</span> <span class='hs-layout'>(</span><span class='hs-varid'>f</span> <span class='hs-varop'>.</span> <span class='hs-conid'>NonEmpty</span><span class='hs-varop'>.</span><span class='hs-varid'>toList</span> <span class='hs-varop'>.</span> <span class='hs-varid'>g</span><span class='hs-layout'>)</span>
<a name="line-167"></a>
<a name="line-168"></a><span class='hs-comment'>------------------------------------------------------------------------------</span>
<a name="line-169"></a><span class='hs-comment'>-- Leftmost and Rightmost</span>
<a name="line-170"></a><span class='hs-comment'>------------------------------------------------------------------------------</span>
<a name="line-171"></a>
<a name="line-172"></a><a name="Leftmost"></a><span class='hs-comment'>-- | Used for 'Control.Lens.Fold.preview'.</span>
<a name="line-173"></a><a name="Leftmost"></a><span class='hs-keyword'>data</span> <span class='hs-conid'>Leftmost</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>LPure</span> <span class='hs-keyglyph'>|</span> <span class='hs-conid'>LLeaf</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>|</span> <span class='hs-conid'>LStep</span> <span class='hs-layout'>(</span><span class='hs-conid'>Leftmost</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span>
<a name="line-174"></a>
<a name="line-175"></a><a name="instance%20Semigroup%20(Leftmost%20a)"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>Semigroup</span> <span class='hs-layout'>(</span><span class='hs-conid'>Leftmost</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-176"></a> <span class='hs-layout'>(</span><span class='hs-varop'><></span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>mappend</span>
<a name="line-177"></a> <span class='hs-comment'>{-# INLINE (<>) #-}</span>
<a name="line-178"></a>
<a name="line-179"></a><a name="instance%20Monoid%20(Leftmost%20a)"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>Monoid</span> <span class='hs-layout'>(</span><span class='hs-conid'>Leftmost</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-180"></a> <span class='hs-varid'>mempty</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>LPure</span>
<a name="line-181"></a> <span class='hs-comment'>{-# INLINE mempty #-}</span>
<a name="line-182"></a> <span class='hs-varid'>mappend</span> <span class='hs-varid'>x</span> <span class='hs-varid'>y</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>LStep</span> <span class='hs-varop'>$</span> <span class='hs-keyword'>case</span> <span class='hs-varid'>x</span> <span class='hs-keyword'>of</span>
<a name="line-183"></a> <span class='hs-conid'>LPure</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>y</span>
<a name="line-184"></a> <span class='hs-conid'>LLeaf</span> <span class='hs-keyword'>_</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>x</span>
<a name="line-185"></a> <span class='hs-conid'>LStep</span> <span class='hs-varid'>x'</span> <span class='hs-keyglyph'>-></span> <span class='hs-keyword'>case</span> <span class='hs-varid'>y</span> <span class='hs-keyword'>of</span>
<a name="line-186"></a> <span class='hs-comment'>-- The last two cases make firstOf produce a Just as soon as any element</span>
<a name="line-187"></a> <span class='hs-comment'>-- is encountered, and possibly serve as a micro-optimisation; this</span>
<a name="line-188"></a> <span class='hs-comment'>-- behaviour can be disabled by replacing them with _ -> mappend x y'.</span>
<a name="line-189"></a> <span class='hs-comment'>-- Note that this means that firstOf (backwards folded) [1..] is Just _|_.</span>
<a name="line-190"></a> <span class='hs-conid'>LPure</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>x'</span>
<a name="line-191"></a> <span class='hs-conid'>LLeaf</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>LLeaf</span> <span class='hs-varop'>$</span> <span class='hs-varid'>fromMaybe</span> <span class='hs-varid'>a</span> <span class='hs-layout'>(</span><span class='hs-varid'>getLeftmost</span> <span class='hs-varid'>x'</span><span class='hs-layout'>)</span>
<a name="line-192"></a> <span class='hs-conid'>LStep</span> <span class='hs-varid'>y'</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>mappend</span> <span class='hs-varid'>x'</span> <span class='hs-varid'>y'</span>
<a name="line-193"></a>
<a name="line-194"></a><a name="getLeftmost"></a><span class='hs-comment'>-- | Extract the 'Leftmost' element. This will fairly eagerly determine that it can return 'Just'</span>
<a name="line-195"></a><span class='hs-comment'>-- the moment it sees any element at all.</span>
<a name="line-196"></a><span class='hs-definition'>getLeftmost</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Leftmost</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Maybe</span> <span class='hs-varid'>a</span>
<a name="line-197"></a><span class='hs-definition'>getLeftmost</span> <span class='hs-conid'>LPure</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Nothing</span>
<a name="line-198"></a><span class='hs-definition'>getLeftmost</span> <span class='hs-layout'>(</span><span class='hs-conid'>LLeaf</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Just</span> <span class='hs-varid'>a</span>
<a name="line-199"></a><span class='hs-definition'>getLeftmost</span> <span class='hs-layout'>(</span><span class='hs-conid'>LStep</span> <span class='hs-varid'>x</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>getLeftmost</span> <span class='hs-varid'>x</span>
<a name="line-200"></a>
<a name="line-201"></a><a name="Rightmost"></a><span class='hs-comment'>-- | Used for 'Control.Lens.Fold.lastOf'.</span>
<a name="line-202"></a><a name="Rightmost"></a><span class='hs-keyword'>data</span> <span class='hs-conid'>Rightmost</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>RPure</span> <span class='hs-keyglyph'>|</span> <span class='hs-conid'>RLeaf</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>|</span> <span class='hs-conid'>RStep</span> <span class='hs-layout'>(</span><span class='hs-conid'>Rightmost</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span>
<a name="line-203"></a>
<a name="line-204"></a><a name="instance%20Semigroup%20(Rightmost%20a)"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>Semigroup</span> <span class='hs-layout'>(</span><span class='hs-conid'>Rightmost</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-205"></a> <span class='hs-layout'>(</span><span class='hs-varop'><></span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>mappend</span>
<a name="line-206"></a> <span class='hs-comment'>{-# INLINE (<>) #-}</span>
<a name="line-207"></a>
<a name="line-208"></a><a name="instance%20Monoid%20(Rightmost%20a)"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>Monoid</span> <span class='hs-layout'>(</span><span class='hs-conid'>Rightmost</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-209"></a> <span class='hs-varid'>mempty</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>RPure</span>
<a name="line-210"></a> <span class='hs-comment'>{-# INLINE mempty #-}</span>
<a name="line-211"></a> <span class='hs-varid'>mappend</span> <span class='hs-varid'>x</span> <span class='hs-varid'>y</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>RStep</span> <span class='hs-varop'>$</span> <span class='hs-keyword'>case</span> <span class='hs-varid'>y</span> <span class='hs-keyword'>of</span>
<a name="line-212"></a> <span class='hs-conid'>RPure</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>x</span>
<a name="line-213"></a> <span class='hs-conid'>RLeaf</span> <span class='hs-keyword'>_</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>y</span>
<a name="line-214"></a> <span class='hs-conid'>RStep</span> <span class='hs-varid'>y'</span> <span class='hs-keyglyph'>-></span> <span class='hs-keyword'>case</span> <span class='hs-varid'>x</span> <span class='hs-keyword'>of</span>
<a name="line-215"></a> <span class='hs-comment'>-- The last two cases make lastOf produce a Just as soon as any element</span>
<a name="line-216"></a> <span class='hs-comment'>-- is encountered, and possibly serve as a micro-optimisation; this</span>
<a name="line-217"></a> <span class='hs-comment'>-- behaviour can be disabled by replacing them with _ -> mappend x y'.</span>
<a name="line-218"></a> <span class='hs-comment'>-- Note that this means that lastOf folded [1..] is Just _|_.</span>
<a name="line-219"></a> <span class='hs-conid'>RPure</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>y'</span>
<a name="line-220"></a> <span class='hs-conid'>RLeaf</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>RLeaf</span> <span class='hs-varop'>$</span> <span class='hs-varid'>fromMaybe</span> <span class='hs-varid'>a</span> <span class='hs-layout'>(</span><span class='hs-varid'>getRightmost</span> <span class='hs-varid'>y'</span><span class='hs-layout'>)</span>
<a name="line-221"></a> <span class='hs-conid'>RStep</span> <span class='hs-varid'>x'</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>mappend</span> <span class='hs-varid'>x'</span> <span class='hs-varid'>y'</span>
<a name="line-222"></a>
<a name="line-223"></a><a name="getRightmost"></a><span class='hs-comment'>-- | Extract the 'Rightmost' element. This will fairly eagerly determine that it can return 'Just'</span>
<a name="line-224"></a><span class='hs-comment'>-- the moment it sees any element at all.</span>
<a name="line-225"></a><span class='hs-definition'>getRightmost</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Rightmost</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Maybe</span> <span class='hs-varid'>a</span>
<a name="line-226"></a><span class='hs-definition'>getRightmost</span> <span class='hs-conid'>RPure</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Nothing</span>
<a name="line-227"></a><span class='hs-definition'>getRightmost</span> <span class='hs-layout'>(</span><span class='hs-conid'>RLeaf</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Just</span> <span class='hs-varid'>a</span>
<a name="line-228"></a><span class='hs-definition'>getRightmost</span> <span class='hs-layout'>(</span><span class='hs-conid'>RStep</span> <span class='hs-varid'>x</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>getRightmost</span> <span class='hs-varid'>x</span>
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