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<pre><a name="line-1"></a><span class='hs-keyword'>module</span> <span class='hs-conid'>OrdList</span> <span class='hs-layout'>(</span>
<a name="line-2"></a> <span class='hs-conid'>OrdList</span><span class='hs-layout'>,</span>
<a name="line-3"></a> <span class='hs-varid'>nilOL</span><span class='hs-layout'>,</span> <span class='hs-varid'>isNilOL</span><span class='hs-layout'>,</span> <span class='hs-varid'>unitOL</span><span class='hs-layout'>,</span> <span class='hs-varid'>appOL</span><span class='hs-layout'>,</span> <span class='hs-varid'>consOL</span><span class='hs-layout'>,</span> <span class='hs-varid'>snocOL</span><span class='hs-layout'>,</span> <span class='hs-varid'>concatOL</span><span class='hs-layout'>,</span>
<a name="line-4"></a> <span class='hs-varid'>mapOL</span><span class='hs-layout'>,</span> <span class='hs-varid'>fromOL</span><span class='hs-layout'>,</span> <span class='hs-varid'>toOL</span><span class='hs-layout'>,</span> <span class='hs-varid'>foldrOL</span><span class='hs-layout'>,</span> <span class='hs-varid'>foldlOL</span>
<a name="line-5"></a><span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-6"></a>
<a name="line-7"></a><span class='hs-keyword'>infixl</span> <span class='hs-num'>5</span> <span class='hs-varop'>`appOL`</span>
<a name="line-8"></a><span class='hs-keyword'>infixl</span> <span class='hs-num'>5</span> <span class='hs-varop'>`snocOL`</span>
<a name="line-9"></a><span class='hs-keyword'>infixr</span> <span class='hs-num'>5</span> <span class='hs-varop'>`consOL`</span>
<a name="line-10"></a>
<a name="line-11"></a><a name="OrdList"></a><span class='hs-keyword'>data</span> <span class='hs-conid'>OrdList</span> <span class='hs-varid'>a</span>
<a name="line-12"></a> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Many</span> <span class='hs-keyglyph'>[</span><span class='hs-varid'>a</span><span class='hs-keyglyph'>]</span> <span class='hs-comment'>-- Invariant: non-empty</span>
<a name="line-13"></a> <span class='hs-keyglyph'>|</span> <span class='hs-conid'>Two</span> <span class='hs-layout'>(</span><span class='hs-conid'>OrdList</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-comment'>-- Invariant: non-empty</span>
<a name="line-14"></a> <span class='hs-layout'>(</span><span class='hs-conid'>OrdList</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-comment'>-- Invariant: non-empty</span>
<a name="line-15"></a> <span class='hs-keyglyph'>|</span> <span class='hs-conid'>One</span> <span class='hs-varid'>a</span>
<a name="line-16"></a> <span class='hs-keyglyph'>|</span> <span class='hs-conid'>None</span>
<a name="line-17"></a>
<a name="line-18"></a><a name="nilOL"></a><span class='hs-definition'>nilOL</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>OrdList</span> <span class='hs-varid'>a</span>
<a name="line-19"></a><a name="isNilOL"></a><span class='hs-definition'>isNilOL</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>OrdList</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Bool</span>
<a name="line-20"></a>
<a name="line-21"></a><a name="unitOL"></a><span class='hs-definition'>unitOL</span> <span class='hs-keyglyph'>::</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>OrdList</span> <span class='hs-varid'>a</span>
<a name="line-22"></a><a name="snocOL"></a><span class='hs-definition'>snocOL</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>OrdList</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>OrdList</span> <span class='hs-varid'>a</span>
<a name="line-23"></a><a name="consOL"></a><span class='hs-definition'>consOL</span> <span class='hs-keyglyph'>::</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>OrdList</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>OrdList</span> <span class='hs-varid'>a</span>
<a name="line-24"></a><a name="appOL"></a><span class='hs-definition'>appOL</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>OrdList</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>OrdList</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>OrdList</span> <span class='hs-varid'>a</span>
<a name="line-25"></a><a name="concatOL"></a><span class='hs-definition'>concatOL</span> <span class='hs-keyglyph'>::</span> <span class='hs-keyglyph'>[</span><span class='hs-conid'>OrdList</span> <span class='hs-varid'>a</span><span class='hs-keyglyph'>]</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>OrdList</span> <span class='hs-varid'>a</span>
<a name="line-26"></a>
<a name="line-27"></a><span class='hs-definition'>nilOL</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>None</span>
<a name="line-28"></a><span class='hs-definition'>unitOL</span> <span class='hs-keyword'>as</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>One</span> <span class='hs-keyword'>as</span>
<a name="line-29"></a><span class='hs-definition'>snocOL</span> <span class='hs-conid'>None</span> <span class='hs-varid'>b</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>One</span> <span class='hs-varid'>b</span>
<a name="line-30"></a><span class='hs-definition'>snocOL</span> <span class='hs-keyword'>as</span> <span class='hs-varid'>b</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Two</span> <span class='hs-keyword'>as</span> <span class='hs-layout'>(</span><span class='hs-conid'>One</span> <span class='hs-varid'>b</span><span class='hs-layout'>)</span>
<a name="line-31"></a><span class='hs-definition'>consOL</span> <span class='hs-varid'>a</span> <span class='hs-conid'>None</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>One</span> <span class='hs-varid'>a</span>
<a name="line-32"></a><span class='hs-definition'>consOL</span> <span class='hs-varid'>a</span> <span class='hs-varid'>bs</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Two</span> <span class='hs-layout'>(</span><span class='hs-conid'>One</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-varid'>bs</span>
<a name="line-33"></a><span class='hs-definition'>concatOL</span> <span class='hs-varid'>aas</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>foldr</span> <span class='hs-varid'>appOL</span> <span class='hs-conid'>None</span> <span class='hs-varid'>aas</span>
<a name="line-34"></a>
<a name="line-35"></a><span class='hs-definition'>isNilOL</span> <span class='hs-conid'>None</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>True</span>
<a name="line-36"></a><span class='hs-definition'>isNilOL</span> <span class='hs-keyword'>_</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>False</span>
<a name="line-37"></a>
<a name="line-38"></a><span class='hs-definition'>appOL</span> <span class='hs-conid'>None</span> <span class='hs-varid'>bs</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>bs</span>
<a name="line-39"></a><span class='hs-definition'>appOL</span> <span class='hs-keyword'>as</span> <span class='hs-conid'>None</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>as</span>
<a name="line-40"></a><span class='hs-definition'>appOL</span> <span class='hs-keyword'>as</span> <span class='hs-varid'>bs</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Two</span> <span class='hs-keyword'>as</span> <span class='hs-varid'>bs</span>
<a name="line-41"></a>
<a name="line-42"></a><a name="mapOL"></a><span class='hs-definition'>mapOL</span> <span class='hs-keyglyph'>::</span> <span class='hs-layout'>(</span><span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>b</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>OrdList</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>OrdList</span> <span class='hs-varid'>b</span>
<a name="line-43"></a><span class='hs-definition'>mapOL</span> <span class='hs-keyword'>_</span> <span class='hs-conid'>None</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>None</span>
<a name="line-44"></a><span class='hs-definition'>mapOL</span> <span class='hs-varid'>f</span> <span class='hs-layout'>(</span><span class='hs-conid'>One</span> <span class='hs-varid'>x</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>One</span> <span class='hs-layout'>(</span><span class='hs-varid'>f</span> <span class='hs-varid'>x</span><span class='hs-layout'>)</span>
<a name="line-45"></a><span class='hs-definition'>mapOL</span> <span class='hs-varid'>f</span> <span class='hs-layout'>(</span><span class='hs-conid'>Two</span> <span class='hs-varid'>x</span> <span class='hs-varid'>y</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Two</span> <span class='hs-layout'>(</span><span class='hs-varid'>mapOL</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-varid'>mapOL</span> <span class='hs-varid'>f</span> <span class='hs-varid'>y</span><span class='hs-layout'>)</span>
<a name="line-46"></a><span class='hs-definition'>mapOL</span> <span class='hs-varid'>f</span> <span class='hs-layout'>(</span><span class='hs-conid'>Many</span> <span class='hs-varid'>xs</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Many</span> <span class='hs-layout'>(</span><span class='hs-varid'>map</span> <span class='hs-varid'>f</span> <span class='hs-varid'>xs</span><span class='hs-layout'>)</span>
<a name="line-47"></a>
<a name="line-48"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>Functor</span> <span class='hs-conid'>OrdList</span> <span class='hs-keyword'>where</span>
<a name="line-49"></a> <span class='hs-varid'>fmap</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>mapOL</span>
<a name="line-50"></a>
<a name="line-51"></a><a name="foldrOL"></a><span class='hs-definition'>foldrOL</span> <span class='hs-keyglyph'>::</span> <span class='hs-layout'>(</span><span class='hs-varid'>a</span><span class='hs-keyglyph'>-></span><span class='hs-varid'>b</span><span class='hs-keyglyph'>-></span><span class='hs-varid'>b</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>b</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>OrdList</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>b</span>
<a name="line-52"></a><span class='hs-definition'>foldrOL</span> <span class='hs-keyword'>_</span> <span class='hs-varid'>z</span> <span class='hs-conid'>None</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>z</span>
<a name="line-53"></a><span class='hs-definition'>foldrOL</span> <span class='hs-varid'>k</span> <span class='hs-varid'>z</span> <span class='hs-layout'>(</span><span class='hs-conid'>One</span> <span class='hs-varid'>x</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>k</span> <span class='hs-varid'>x</span> <span class='hs-varid'>z</span>
<a name="line-54"></a><span class='hs-definition'>foldrOL</span> <span class='hs-varid'>k</span> <span class='hs-varid'>z</span> <span class='hs-layout'>(</span><span class='hs-conid'>Two</span> <span class='hs-varid'>b1</span> <span class='hs-varid'>b2</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>foldrOL</span> <span class='hs-varid'>k</span> <span class='hs-layout'>(</span><span class='hs-varid'>foldrOL</span> <span class='hs-varid'>k</span> <span class='hs-varid'>z</span> <span class='hs-varid'>b2</span><span class='hs-layout'>)</span> <span class='hs-varid'>b1</span>
<a name="line-55"></a><span class='hs-definition'>foldrOL</span> <span class='hs-varid'>k</span> <span class='hs-varid'>z</span> <span class='hs-layout'>(</span><span class='hs-conid'>Many</span> <span class='hs-varid'>xs</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>foldr</span> <span class='hs-varid'>k</span> <span class='hs-varid'>z</span> <span class='hs-varid'>xs</span>
<a name="line-56"></a>
<a name="line-57"></a><a name="foldlOL"></a><span class='hs-definition'>foldlOL</span> <span class='hs-keyglyph'>::</span> <span class='hs-layout'>(</span><span class='hs-varid'>b</span><span class='hs-keyglyph'>-></span><span class='hs-varid'>a</span><span class='hs-keyglyph'>-></span><span class='hs-varid'>b</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>b</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>OrdList</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>b</span>
<a name="line-58"></a><span class='hs-definition'>foldlOL</span> <span class='hs-keyword'>_</span> <span class='hs-varid'>z</span> <span class='hs-conid'>None</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>z</span>
<a name="line-59"></a><span class='hs-definition'>foldlOL</span> <span class='hs-varid'>k</span> <span class='hs-varid'>z</span> <span class='hs-layout'>(</span><span class='hs-conid'>One</span> <span class='hs-varid'>x</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>k</span> <span class='hs-varid'>z</span> <span class='hs-varid'>x</span>
<a name="line-60"></a><span class='hs-definition'>foldlOL</span> <span class='hs-varid'>k</span> <span class='hs-varid'>z</span> <span class='hs-layout'>(</span><span class='hs-conid'>Two</span> <span class='hs-varid'>b1</span> <span class='hs-varid'>b2</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>foldlOL</span> <span class='hs-varid'>k</span> <span class='hs-layout'>(</span><span class='hs-varid'>foldlOL</span> <span class='hs-varid'>k</span> <span class='hs-varid'>z</span> <span class='hs-varid'>b1</span><span class='hs-layout'>)</span> <span class='hs-varid'>b2</span>
<a name="line-61"></a><span class='hs-definition'>foldlOL</span> <span class='hs-varid'>k</span> <span class='hs-varid'>z</span> <span class='hs-layout'>(</span><span class='hs-conid'>Many</span> <span class='hs-varid'>xs</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>foldl</span> <span class='hs-varid'>k</span> <span class='hs-varid'>z</span> <span class='hs-varid'>xs</span>
<a name="line-62"></a>
<a name="line-63"></a><a name="fromOL"></a><span class='hs-definition'>fromOL</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>OrdList</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-keyglyph'>[</span><span class='hs-varid'>a</span><span class='hs-keyglyph'>]</span>
<a name="line-64"></a><span class='hs-definition'>fromOL</span> <span class='hs-varid'>ol</span>
<a name="line-65"></a> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>flat</span> <span class='hs-varid'>ol</span> <span class='hs-conid'>[]</span>
<a name="line-66"></a> <span class='hs-keyword'>where</span>
<a name="line-67"></a> <span class='hs-varid'>flat</span> <span class='hs-conid'>None</span> <span class='hs-varid'>rest</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>rest</span>
<a name="line-68"></a> <span class='hs-varid'>flat</span> <span class='hs-layout'>(</span><span class='hs-conid'>One</span> <span class='hs-varid'>x</span><span class='hs-layout'>)</span> <span class='hs-varid'>rest</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>x</span><span class='hs-conop'>:</span><span class='hs-varid'>rest</span>
<a name="line-69"></a> <span class='hs-varid'>flat</span> <span class='hs-layout'>(</span><span class='hs-conid'>Two</span> <span class='hs-varid'>a</span> <span class='hs-varid'>b</span><span class='hs-layout'>)</span> <span class='hs-varid'>rest</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>flat</span> <span class='hs-varid'>a</span> <span class='hs-layout'>(</span><span class='hs-varid'>flat</span> <span class='hs-varid'>b</span> <span class='hs-varid'>rest</span><span class='hs-layout'>)</span>
<a name="line-70"></a> <span class='hs-varid'>flat</span> <span class='hs-layout'>(</span><span class='hs-conid'>Many</span> <span class='hs-varid'>xs</span><span class='hs-layout'>)</span> <span class='hs-varid'>rest</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>xs</span> <span class='hs-varop'>++</span> <span class='hs-varid'>rest</span>
<a name="line-71"></a>
<a name="line-72"></a><a name="toOL"></a><span class='hs-definition'>toOL</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'>OrdList</span> <span class='hs-varid'>a</span>
<a name="line-73"></a><span class='hs-definition'>toOL</span> <span class='hs-conid'>[]</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>None</span>
<a name="line-74"></a><span class='hs-definition'>toOL</span> <span class='hs-varid'>xs</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Many</span> <span class='hs-varid'>xs</span>
</pre>\end{code}
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