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<pre><a name="line-1"></a><span class='hs-comment'>{- |
<a name="line-2"></a> This module provides the 'Str' data type, which is used by the
<a name="line-3"></a> underlying 'uniplate' and 'biplate' methods. It should not
<a name="line-4"></a> be used directly under normal circumstances.
<a name="line-5"></a>-}</span>
<a name="line-6"></a>
<a name="line-7"></a><span class='hs-keyword'>module</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Generics</span><span class='hs-varop'>.</span><span class='hs-conid'>Str</span> <span class='hs-keyword'>where</span>
<a name="line-8"></a>
<a name="line-9"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Generics</span><span class='hs-varop'>.</span><span class='hs-conid'>PlateInternal</span>
<a name="line-10"></a>
<a name="line-11"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Traversable</span>
<a name="line-12"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Foldable</span>
<a name="line-13"></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-14"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Monoid</span>
<a name="line-15"></a>
<a name="line-16"></a><span class='hs-comment'>-- * The Data Type</span>
<a name="line-17"></a>
<a name="line-18"></a><a name="Str"></a><span class='hs-keyword'>data</span> <span class='hs-conid'>Str</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Zero</span> <span class='hs-keyglyph'>|</span> <span class='hs-conid'>One</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>|</span> <span class='hs-conid'>Two</span> <span class='hs-layout'>(</span><span class='hs-conid'>Str</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-layout'>(</span><span class='hs-conid'>Str</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span>
<a name="line-19"></a> <span class='hs-keyword'>deriving</span> <span class='hs-conid'>Show</span>
<a name="line-20"></a>
<a name="line-21"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>Eq</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>=></span> <span class='hs-conid'>Eq</span> <span class='hs-layout'>(</span><span class='hs-conid'>Str</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-22"></a> <span class='hs-conid'>Zero</span> <span class='hs-varop'>==</span> <span class='hs-conid'>Zero</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>True</span>
<a name="line-23"></a> <span class='hs-conid'>One</span> <span class='hs-varid'>x</span> <span class='hs-varop'>==</span> <span class='hs-conid'>One</span> <span class='hs-varid'>y</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>x</span> <span class='hs-varop'>==</span> <span class='hs-varid'>y</span>
<a name="line-24"></a> <span class='hs-conid'>Two</span> <span class='hs-varid'>x1</span> <span class='hs-varid'>x2</span> <span class='hs-varop'>==</span> <span class='hs-conid'>Two</span> <span class='hs-varid'>y1</span> <span class='hs-varid'>y2</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>x1</span> <span class='hs-varop'>==</span> <span class='hs-varid'>y1</span> <span class='hs-varop'>&&</span> <span class='hs-varid'>x2</span> <span class='hs-varop'>==</span> <span class='hs-varid'>y2</span>
<a name="line-25"></a> <span class='hs-keyword'>_</span> <span class='hs-varop'>==</span> <span class='hs-keyword'>_</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>False</span>
<a name="line-26"></a>
<a name="line-27"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>Functor</span> <span class='hs-conid'>Str</span> <span class='hs-keyword'>where</span>
<a name="line-28"></a> <span class='hs-varid'>fmap</span> <span class='hs-varid'>f</span> <span class='hs-conid'>Zero</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Zero</span>
<a name="line-29"></a> <span class='hs-varid'>fmap</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-30"></a> <span class='hs-varid'>fmap</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'>fmap</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'>fmap</span> <span class='hs-varid'>f</span> <span class='hs-varid'>y</span><span class='hs-layout'>)</span>
<a name="line-31"></a>
<a name="line-32"></a>
<a name="line-33"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>Foldable</span> <span class='hs-conid'>Str</span> <span class='hs-keyword'>where</span>
<a name="line-34"></a> <span class='hs-varid'>foldMap</span> <span class='hs-varid'>m</span> <span class='hs-conid'>Zero</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>mempty</span>
<a name="line-35"></a> <span class='hs-varid'>foldMap</span> <span class='hs-varid'>m</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'>m</span> <span class='hs-varid'>x</span>
<a name="line-36"></a> <span class='hs-varid'>foldMap</span> <span class='hs-varid'>m</span> <span class='hs-layout'>(</span><span class='hs-conid'>Two</span> <span class='hs-varid'>l</span> <span class='hs-varid'>r</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>foldMap</span> <span class='hs-varid'>m</span> <span class='hs-varid'>l</span> <span class='hs-varop'>`mappend`</span> <span class='hs-varid'>foldMap</span> <span class='hs-varid'>m</span> <span class='hs-varid'>r</span>
<a name="line-37"></a>
<a name="line-38"></a>
<a name="line-39"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>Traversable</span> <span class='hs-conid'>Str</span> <span class='hs-keyword'>where</span>
<a name="line-40"></a> <span class='hs-varid'>traverse</span> <span class='hs-varid'>f</span> <span class='hs-conid'>Zero</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>pure</span> <span class='hs-conid'>Zero</span>
<a name="line-41"></a> <span class='hs-varid'>traverse</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-varop'><$></span> <span class='hs-varid'>f</span> <span class='hs-varid'>x</span>
<a name="line-42"></a> <span class='hs-varid'>traverse</span> <span class='hs-varid'>f</span> <span class='hs-layout'>(</span><span class='hs-conid'>Two</span> <span class='hs-varid'>x</span> <span class='hs-varid'>y</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Two</span> <span class='hs-varop'><$></span> <span class='hs-varid'>traverse</span> <span class='hs-varid'>f</span> <span class='hs-varid'>x</span> <span class='hs-varop'><*></span> <span class='hs-varid'>traverse</span> <span class='hs-varid'>f</span> <span class='hs-varid'>y</span>
<a name="line-43"></a>
<a name="line-44"></a>
<a name="line-45"></a><a name="strType"></a><span class='hs-comment'>-- | Take the type of the method, will crash if called</span>
<a name="line-46"></a><span class='hs-definition'>strType</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Str</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>a</span>
<a name="line-47"></a><span class='hs-definition'>strType</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>error</span> <span class='hs-str'>"Data.Generics.Str.strType: Cannot be called"</span>
<a name="line-48"></a>
<a name="line-49"></a>
<a name="line-50"></a><a name="strList"></a><span class='hs-comment'>-- | Convert a 'Str' to a list, assumes the value was created</span>
<a name="line-51"></a><span class='hs-comment'>-- with 'listStr'</span>
<a name="line-52"></a><span class='hs-definition'>strList</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Str</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-53"></a><span class='hs-definition'>strList</span> <span class='hs-varid'>x</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>builder</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-54"></a> <span class='hs-keyword'>where</span>
<a name="line-55"></a> <span class='hs-varid'>f</span> <span class='hs-layout'>(</span><span class='hs-conid'>Two</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'>xs</span><span class='hs-layout'>)</span> <span class='hs-varid'>cons</span> <span class='hs-varid'>nil</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>x</span> <span class='hs-varop'>`cons`</span> <span class='hs-varid'>f</span> <span class='hs-varid'>xs</span> <span class='hs-varid'>cons</span> <span class='hs-varid'>nil</span>
<a name="line-56"></a> <span class='hs-varid'>f</span> <span class='hs-conid'>Zero</span> <span class='hs-varid'>cons</span> <span class='hs-varid'>nil</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>nil</span>
<a name="line-57"></a>
<a name="line-58"></a>
<a name="line-59"></a><a name="listStr"></a><span class='hs-comment'>-- | Convert a list to a 'Str'</span>
<a name="line-60"></a><span class='hs-definition'>listStr</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'>Str</span> <span class='hs-varid'>a</span>
<a name="line-61"></a><span class='hs-definition'>listStr</span> <span class='hs-layout'>(</span><span class='hs-varid'>x</span><span class='hs-conop'>:</span><span class='hs-varid'>xs</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-conid'>One</span> <span class='hs-varid'>x</span><span class='hs-layout'>)</span> <span class='hs-layout'>(</span><span class='hs-varid'>listStr</span> <span class='hs-varid'>xs</span><span class='hs-layout'>)</span>
<a name="line-62"></a><span class='hs-definition'>listStr</span> <span class='hs-conid'>[]</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Zero</span>
<a name="line-63"></a>
<a name="line-64"></a>
<a name="line-65"></a><a name="strStructure"></a><span class='hs-comment'>-- | Transform a 'Str' to a list, and back again, in a structure</span>
<a name="line-66"></a><span class='hs-comment'>-- preserving way. The output and input lists must be equal in</span>
<a name="line-67"></a><span class='hs-comment'>-- length.</span>
<a name="line-68"></a><span class='hs-definition'>strStructure</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Str</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>[</span><span class='hs-varid'>a</span><span class='hs-keyglyph'>]</span><span class='hs-layout'>,</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'>Str</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span>
<a name="line-69"></a><span class='hs-definition'>strStructure</span> <span class='hs-varid'>x</span> <span class='hs-keyglyph'>=</span> <span class='hs-layout'>(</span><span class='hs-varid'>g</span> <span class='hs-varid'>x</span> <span class='hs-conid'>[]</span><span class='hs-layout'>,</span> <span class='hs-varid'>fst</span> <span class='hs-varop'>.</span> <span class='hs-varid'>f</span> <span class='hs-varid'>x</span><span class='hs-layout'>)</span>
<a name="line-70"></a> <span class='hs-keyword'>where</span>
<a name="line-71"></a> <span class='hs-varid'>g</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Str</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> <span class='hs-keyglyph'>-></span> <span class='hs-keyglyph'>[</span><span class='hs-varid'>a</span><span class='hs-keyglyph'>]</span>
<a name="line-72"></a> <span class='hs-varid'>g</span> <span class='hs-conid'>Zero</span> <span class='hs-varid'>xs</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>xs</span>
<a name="line-73"></a> <span class='hs-varid'>g</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'>xs</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>x</span><span class='hs-conop'>:</span><span class='hs-varid'>xs</span>
<a name="line-74"></a> <span class='hs-varid'>g</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'>xs</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>g</span> <span class='hs-varid'>a</span> <span class='hs-layout'>(</span><span class='hs-varid'>g</span> <span class='hs-varid'>b</span> <span class='hs-varid'>xs</span><span class='hs-layout'>)</span>
<a name="line-75"></a>
<a name="line-76"></a> <span class='hs-varid'>f</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Str</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> <span class='hs-keyglyph'>-></span> <span class='hs-layout'>(</span><span class='hs-conid'>Str</span> <span class='hs-varid'>a</span><span class='hs-layout'>,</span> <span class='hs-keyglyph'>[</span><span class='hs-varid'>a</span><span class='hs-keyglyph'>]</span><span class='hs-layout'>)</span>
<a name="line-77"></a> <span class='hs-varid'>f</span> <span class='hs-conid'>Zero</span> <span class='hs-varid'>rs</span> <span class='hs-keyglyph'>=</span> <span class='hs-layout'>(</span><span class='hs-conid'>Zero</span><span class='hs-layout'>,</span> <span class='hs-varid'>rs</span><span class='hs-layout'>)</span>
<a name="line-78"></a> <span class='hs-varid'>f</span> <span class='hs-layout'>(</span><span class='hs-conid'>One</span> <span class='hs-keyword'>_</span><span class='hs-layout'>)</span> <span class='hs-layout'>(</span><span class='hs-varid'>r</span><span class='hs-conop'>:</span><span class='hs-varid'>rs</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-layout'>(</span><span class='hs-conid'>One</span> <span class='hs-varid'>r</span><span class='hs-layout'>,</span> <span class='hs-varid'>rs</span><span class='hs-layout'>)</span>
<a name="line-79"></a> <span class='hs-varid'>f</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'>rs1</span> <span class='hs-keyglyph'>=</span> <span class='hs-layout'>(</span><span class='hs-conid'>Two</span> <span class='hs-varid'>a2</span> <span class='hs-varid'>b2</span><span class='hs-layout'>,</span> <span class='hs-varid'>rs3</span><span class='hs-layout'>)</span>
<a name="line-80"></a> <span class='hs-keyword'>where</span>
<a name="line-81"></a> <span class='hs-layout'>(</span><span class='hs-varid'>a2</span><span class='hs-layout'>,</span><span class='hs-varid'>rs2</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>f</span> <span class='hs-varid'>a</span> <span class='hs-varid'>rs1</span>
<a name="line-82"></a> <span class='hs-layout'>(</span><span class='hs-varid'>b2</span><span class='hs-layout'>,</span><span class='hs-varid'>rs3</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>f</span> <span class='hs-varid'>b</span> <span class='hs-varid'>rs2</span>
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