<?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://code.haskell.org/~malcolm/hscolour/ --> <title>src/full/Agda/Utils/TestHelpers.hs</title> <link type='text/css' rel='stylesheet' href='hscolour.css' /> </head> <body> <pre><a name="line-1"></a><span class='hs-comment'>-- | Some functions and generators suitable for writing QuickCheck</span> <a name="line-2"></a><span class='hs-comment'>-- properties.</span> <a name="line-3"></a> <a name="line-4"></a><span class='hs-keyword'>module</span> <span class='hs-conid'>Agda</span><span class='hs-varop'>.</span><span class='hs-conid'>Utils</span><span class='hs-varop'>.</span><span class='hs-conid'>TestHelpers</span> <a name="line-5"></a> <span class='hs-layout'>(</span> <span class='hs-comment'>-- * Algebraic properties</span> <a name="line-6"></a> <span class='hs-varid'>associative</span> <a name="line-7"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>commutative</span> <a name="line-8"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>isZero</span> <a name="line-9"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>identity</span> <a name="line-10"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>leftDistributive</span> <a name="line-11"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>rightDistributive</span> <a name="line-12"></a> <span class='hs-comment'>-- * Generators</span> <a name="line-13"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>natural</span> <a name="line-14"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>positive</span> <a name="line-15"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>maybeGen</span> <a name="line-16"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>maybeCoGen</span> <a name="line-17"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>listOfElements</span> <a name="line-18"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>elementsUnlessEmpty</span> <a name="line-19"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>two</span> <a name="line-20"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>three</span> <a name="line-21"></a> <span class='hs-comment'>-- * Test driver.</span> <a name="line-22"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>runTests</span> <a name="line-23"></a> <span class='hs-layout'>)</span> <a name="line-24"></a> <span class='hs-keyword'>where</span> <a name="line-25"></a> <a name="line-26"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Control</span><span class='hs-varop'>.</span><span class='hs-conid'>Monad</span> <a name="line-27"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>List</span> <a name="line-28"></a> <a name="line-29"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Agda</span><span class='hs-varop'>.</span><span class='hs-conid'>Utils</span><span class='hs-varop'>.</span><span class='hs-conid'>QuickCheck</span> <a name="line-30"></a> <a name="line-31"></a><span class='hs-comment'>------------------------------------------------------------------------</span> <a name="line-32"></a><span class='hs-comment'>-- Algebraic properties</span> <a name="line-33"></a> <a name="line-34"></a><span class='hs-comment'>-- | Is the operator associative?</span> <a name="line-35"></a> <a name="line-36"></a><a name="associative"></a><span class='hs-definition'>associative</span> <span class='hs-keyglyph'>::</span> <span class='hs-layout'>(</span><span class='hs-conid'>Arbitrary</span> <span class='hs-varid'>a</span><span class='hs-layout'>,</span> <span class='hs-conid'>Eq</span> <span class='hs-varid'>a</span><span class='hs-layout'>,</span> <span class='hs-conid'>Show</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <a name="line-37"></a> <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'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <a name="line-38"></a> <span class='hs-keyglyph'>-></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-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Bool</span> <a name="line-39"></a><span class='hs-definition'>associative</span> <span class='hs-layout'>(</span><span class='hs-varop'>+</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyglyph'>\</span><span class='hs-varid'>x</span> <span class='hs-varid'>y</span> <span class='hs-varid'>z</span> <span class='hs-keyglyph'>-></span> <a name="line-40"></a> <span class='hs-varid'>x</span> <span class='hs-varop'>+</span> <span class='hs-layout'>(</span><span class='hs-varid'>y</span> <span class='hs-varop'>+</span> <span class='hs-varid'>z</span><span class='hs-layout'>)</span> <span class='hs-varop'>==</span> <span class='hs-layout'>(</span><span class='hs-varid'>x</span> <span class='hs-varop'>+</span> <span class='hs-varid'>y</span><span class='hs-layout'>)</span> <span class='hs-varop'>+</span> <span class='hs-varid'>z</span> <a name="line-41"></a> <a name="line-42"></a><span class='hs-comment'>-- | Is the operator commutative?</span> <a name="line-43"></a> <a name="line-44"></a><a name="commutative"></a><span class='hs-definition'>commutative</span> <span class='hs-keyglyph'>::</span> <span class='hs-layout'>(</span><span class='hs-conid'>Arbitrary</span> <span class='hs-varid'>a</span><span class='hs-layout'>,</span> <span class='hs-conid'>Eq</span> <span class='hs-varid'>a</span><span class='hs-layout'>,</span> <span class='hs-conid'>Show</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <a name="line-45"></a> <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'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <a name="line-46"></a> <span class='hs-keyglyph'>-></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'>Bool</span> <a name="line-47"></a><span class='hs-definition'>commutative</span> <span class='hs-layout'>(</span><span class='hs-varop'>+</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyglyph'>\</span><span class='hs-varid'>x</span> <span class='hs-varid'>y</span> <span class='hs-keyglyph'>-></span> <a name="line-48"></a> <span class='hs-varid'>x</span> <span class='hs-varop'>+</span> <span class='hs-varid'>y</span> <span class='hs-varop'>==</span> <span class='hs-varid'>y</span> <span class='hs-varop'>+</span> <span class='hs-varid'>x</span> <a name="line-49"></a> <a name="line-50"></a><span class='hs-comment'>-- | Is the element a zero for the operator?</span> <a name="line-51"></a> <a name="line-52"></a><a name="isZero"></a><span class='hs-definition'>isZero</span> <span class='hs-keyglyph'>::</span> <span class='hs-layout'>(</span><span class='hs-conid'>Arbitrary</span> <span class='hs-varid'>a</span><span class='hs-layout'>,</span> <span class='hs-conid'>Eq</span> <span class='hs-varid'>a</span><span class='hs-layout'>,</span> <span class='hs-conid'>Show</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <a name="line-53"></a> <span class='hs-keyglyph'>=></span> <span class='hs-varid'>a</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'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <a name="line-54"></a> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Bool</span> <a name="line-55"></a><span class='hs-definition'>isZero</span> <span class='hs-varid'>zer</span> <span class='hs-layout'>(</span><span class='hs-varop'>*</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyglyph'>\</span><span class='hs-varid'>x</span> <span class='hs-keyglyph'>-></span> <a name="line-56"></a> <span class='hs-layout'>(</span><span class='hs-varid'>zer</span> <span class='hs-varop'>*</span> <span class='hs-varid'>x</span> <span class='hs-varop'>==</span> <span class='hs-varid'>zer</span><span class='hs-layout'>)</span> <a name="line-57"></a> <span class='hs-varop'>&&</span> <a name="line-58"></a> <span class='hs-layout'>(</span><span class='hs-varid'>x</span> <span class='hs-varop'>*</span> <span class='hs-varid'>zer</span> <span class='hs-varop'>==</span> <span class='hs-varid'>zer</span><span class='hs-layout'>)</span> <a name="line-59"></a> <a name="line-60"></a><span class='hs-comment'>-- | Is the element a unit for the operator?</span> <a name="line-61"></a> <a name="line-62"></a><a name="identity"></a><span class='hs-definition'>identity</span> <span class='hs-keyglyph'>::</span> <span class='hs-layout'>(</span><span class='hs-conid'>Arbitrary</span> <span class='hs-varid'>a</span><span class='hs-layout'>,</span> <span class='hs-conid'>Eq</span> <span class='hs-varid'>a</span><span class='hs-layout'>,</span> <span class='hs-conid'>Show</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <a name="line-63"></a> <span class='hs-keyglyph'>=></span> <span class='hs-varid'>a</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'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <a name="line-64"></a> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Bool</span> <a name="line-65"></a><span class='hs-definition'>identity</span> <span class='hs-varid'>one</span> <span class='hs-layout'>(</span><span class='hs-varop'>*</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyglyph'>\</span><span class='hs-varid'>x</span> <span class='hs-keyglyph'>-></span> <a name="line-66"></a> <span class='hs-layout'>(</span><span class='hs-varid'>one</span> <span class='hs-varop'>*</span> <span class='hs-varid'>x</span> <span class='hs-varop'>==</span> <span class='hs-varid'>x</span><span class='hs-layout'>)</span> <a name="line-67"></a> <span class='hs-varop'>&&</span> <a name="line-68"></a> <span class='hs-layout'>(</span><span class='hs-varid'>x</span> <span class='hs-varop'>*</span> <span class='hs-varid'>one</span> <span class='hs-varop'>==</span> <span class='hs-varid'>x</span><span class='hs-layout'>)</span> <a name="line-69"></a> <a name="line-70"></a><span class='hs-comment'>-- | Does the first operator distribute (from the left) over the</span> <a name="line-71"></a><span class='hs-comment'>-- second one?</span> <a name="line-72"></a> <a name="line-73"></a><a name="leftDistributive"></a><span class='hs-definition'>leftDistributive</span> <a name="line-74"></a> <span class='hs-keyglyph'>::</span> <span class='hs-layout'>(</span><span class='hs-conid'>Arbitrary</span> <span class='hs-varid'>a</span><span class='hs-layout'>,</span> <span class='hs-conid'>Eq</span> <span class='hs-varid'>a</span><span class='hs-layout'>,</span> <span class='hs-conid'>Show</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <a name="line-75"></a> <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'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>a</span><span class='hs-layout'>)</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'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <a name="line-76"></a> <span class='hs-keyglyph'>-></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-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Bool</span> <a name="line-77"></a><span class='hs-definition'>leftDistributive</span> <span class='hs-layout'>(</span><span class='hs-varop'>*</span><span class='hs-layout'>)</span> <span class='hs-layout'>(</span><span class='hs-varop'>+</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyglyph'>\</span><span class='hs-varid'>x</span> <span class='hs-varid'>y</span> <span class='hs-varid'>z</span> <span class='hs-keyglyph'>-></span> <a name="line-78"></a> <span class='hs-varid'>x</span> <span class='hs-varop'>*</span> <span class='hs-layout'>(</span><span class='hs-varid'>y</span> <span class='hs-varop'>+</span> <span class='hs-varid'>z</span><span class='hs-layout'>)</span> <span class='hs-varop'>==</span> <span class='hs-layout'>(</span><span class='hs-varid'>x</span> <span class='hs-varop'>*</span> <span class='hs-varid'>y</span><span class='hs-layout'>)</span> <span class='hs-varop'>+</span> <span class='hs-layout'>(</span><span class='hs-varid'>x</span> <span class='hs-varop'>*</span> <span class='hs-varid'>z</span><span class='hs-layout'>)</span> <a name="line-79"></a> <a name="line-80"></a><span class='hs-comment'>-- | Does the first operator distribute (from the right) over the</span> <a name="line-81"></a><span class='hs-comment'>-- second one?</span> <a name="line-82"></a> <a name="line-83"></a><a name="rightDistributive"></a><span class='hs-definition'>rightDistributive</span> <a name="line-84"></a> <span class='hs-keyglyph'>::</span> <span class='hs-layout'>(</span><span class='hs-conid'>Arbitrary</span> <span class='hs-varid'>a</span><span class='hs-layout'>,</span> <span class='hs-conid'>Eq</span> <span class='hs-varid'>a</span><span class='hs-layout'>,</span> <span class='hs-conid'>Show</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <a name="line-85"></a> <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'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>a</span><span class='hs-layout'>)</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'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <a name="line-86"></a> <span class='hs-keyglyph'>-></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-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Bool</span> <a name="line-87"></a><span class='hs-definition'>rightDistributive</span> <span class='hs-layout'>(</span><span class='hs-varop'>*</span><span class='hs-layout'>)</span> <span class='hs-layout'>(</span><span class='hs-varop'>+</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyglyph'>\</span><span class='hs-varid'>x</span> <span class='hs-varid'>y</span> <span class='hs-varid'>z</span> <span class='hs-keyglyph'>-></span> <a name="line-88"></a> <span class='hs-layout'>(</span><span class='hs-varid'>x</span> <span class='hs-varop'>+</span> <span class='hs-varid'>y</span><span class='hs-layout'>)</span> <span class='hs-varop'>*</span> <span class='hs-varid'>z</span> <span class='hs-varop'>==</span> <span class='hs-layout'>(</span><span class='hs-varid'>x</span> <span class='hs-varop'>*</span> <span class='hs-varid'>z</span><span class='hs-layout'>)</span> <span class='hs-varop'>+</span> <span class='hs-layout'>(</span><span class='hs-varid'>y</span> <span class='hs-varop'>*</span> <span class='hs-varid'>z</span><span class='hs-layout'>)</span> <a name="line-89"></a> <a name="line-90"></a><span class='hs-comment'>------------------------------------------------------------------------</span> <a name="line-91"></a><span class='hs-comment'>-- Generators</span> <a name="line-92"></a> <a name="line-93"></a><span class='hs-comment'>-- | Generates natural numbers.</span> <a name="line-94"></a> <a name="line-95"></a><a name="natural"></a><span class='hs-definition'>natural</span> <span class='hs-keyglyph'>::</span> <span class='hs-layout'>(</span><span class='hs-conid'>Integral</span> <span class='hs-varid'>i</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=></span> <span class='hs-conid'>Gen</span> <span class='hs-varid'>i</span> <a name="line-96"></a><span class='hs-definition'>natural</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>fmap</span> <span class='hs-layout'>(</span><span class='hs-varid'>fromInteger</span> <span class='hs-varop'>.</span> <span class='hs-varid'>abs</span><span class='hs-layout'>)</span> <span class='hs-varid'>arbitrary</span> <a name="line-97"></a> <a name="line-98"></a><span class='hs-comment'>-- | Generates positive numbers.</span> <a name="line-99"></a> <a name="line-100"></a><a name="positive"></a><span class='hs-definition'>positive</span> <span class='hs-keyglyph'>::</span> <span class='hs-layout'>(</span><span class='hs-conid'>Integral</span> <span class='hs-varid'>i</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=></span> <span class='hs-conid'>Gen</span> <span class='hs-varid'>i</span> <a name="line-101"></a><span class='hs-definition'>positive</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>fmap</span> <span class='hs-layout'>(</span><span class='hs-layout'>(</span><span class='hs-varop'>+</span> <span class='hs-num'>1</span><span class='hs-layout'>)</span> <span class='hs-varop'>.</span> <span class='hs-varid'>abs</span> <span class='hs-varop'>.</span> <span class='hs-varid'>fromInteger</span><span class='hs-layout'>)</span> <span class='hs-varid'>arbitrary</span> <a name="line-102"></a> <a name="line-103"></a><a name="listOfElements"></a><span class='hs-comment'>-- | Generates a list of elements picked from a given list.</span> <a name="line-104"></a><span class='hs-definition'>listOfElements</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'>Gen</span> <span class='hs-keyglyph'>[</span><span class='hs-varid'>a</span><span class='hs-keyglyph'>]</span> <a name="line-105"></a><span class='hs-definition'>listOfElements</span> <span class='hs-conid'>[]</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>return</span> <span class='hs-conid'>[]</span> <a name="line-106"></a><span class='hs-definition'>listOfElements</span> <span class='hs-varid'>xs</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>listOf</span> <span class='hs-varop'>$</span> <span class='hs-varid'>elements</span> <span class='hs-varid'>xs</span> <a name="line-107"></a> <a name="line-108"></a><span class='hs-comment'>-- | If the given list is non-empty, then an element from the list is</span> <a name="line-109"></a><span class='hs-comment'>-- generated, and otherwise an arbitrary element is generated.</span> <a name="line-110"></a> <a name="line-111"></a><a name="elementsUnlessEmpty"></a><span class='hs-definition'>elementsUnlessEmpty</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Arbitrary</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-conid'>Gen</span> <span class='hs-varid'>a</span> <a name="line-112"></a><span class='hs-definition'>elementsUnlessEmpty</span> <span class='hs-conid'>[]</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>arbitrary</span> <a name="line-113"></a><span class='hs-definition'>elementsUnlessEmpty</span> <span class='hs-varid'>xs</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>elements</span> <span class='hs-varid'>xs</span> <a name="line-114"></a> <a name="line-115"></a><span class='hs-comment'>-- | Generates values of 'Maybe' type, using the given generator to</span> <a name="line-116"></a><span class='hs-comment'>-- generate the contents of the 'Just' constructor.</span> <a name="line-117"></a> <a name="line-118"></a><a name="maybeGen"></a><span class='hs-definition'>maybeGen</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Gen</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Gen</span> <span class='hs-layout'>(</span><span class='hs-conid'>Maybe</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <a name="line-119"></a><span class='hs-definition'>maybeGen</span> <span class='hs-varid'>gen</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>frequency</span> <span class='hs-keyglyph'>[</span> <span class='hs-layout'>(</span><span class='hs-num'>1</span><span class='hs-layout'>,</span> <span class='hs-varid'>return</span> <span class='hs-conid'>Nothing</span><span class='hs-layout'>)</span> <a name="line-120"></a> <span class='hs-layout'>,</span> <span class='hs-layout'>(</span><span class='hs-num'>9</span><span class='hs-layout'>,</span> <span class='hs-varid'>fmap</span> <span class='hs-conid'>Just</span> <span class='hs-varid'>gen</span><span class='hs-layout'>)</span> <a name="line-121"></a> <span class='hs-keyglyph'>]</span> <a name="line-122"></a> <a name="line-123"></a><span class='hs-comment'>-- | 'Coarbitrary' \"generator\" for 'Maybe'.</span> <a name="line-124"></a> <a name="line-125"></a><a name="maybeCoGen"></a><span class='hs-definition'>maybeCoGen</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-conid'>Gen</span> <span class='hs-varid'>b</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Gen</span> <span class='hs-varid'>b</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-></span> <span class='hs-layout'>(</span><span class='hs-conid'>Maybe</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Gen</span> <span class='hs-varid'>b</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Gen</span> <span class='hs-varid'>b</span><span class='hs-layout'>)</span> <a name="line-126"></a><span class='hs-definition'>maybeCoGen</span> <span class='hs-varid'>f</span> <span class='hs-conid'>Nothing</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>variant</span> <span class='hs-num'>0</span> <a name="line-127"></a><span class='hs-definition'>maybeCoGen</span> <span class='hs-varid'>f</span> <span class='hs-layout'>(</span><span class='hs-conid'>Just</span> <span class='hs-varid'>x</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>variant</span> <span class='hs-num'>1</span> <span class='hs-varop'>.</span> <span class='hs-varid'>f</span> <span class='hs-varid'>x</span> <a name="line-128"></a> <a name="line-129"></a><span class='hs-comment'>-- | Generates two elements.</span> <a name="line-130"></a> <a name="line-131"></a><a name="two"></a><span class='hs-definition'>two</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Gen</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Gen</span> <span class='hs-layout'>(</span><span class='hs-varid'>a</span><span class='hs-layout'>,</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <a name="line-132"></a><span class='hs-definition'>two</span> <span class='hs-varid'>gen</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>liftM2</span> <span class='hs-conid'>(,)</span> <span class='hs-varid'>gen</span> <span class='hs-varid'>gen</span> <a name="line-133"></a> <a name="line-134"></a><span class='hs-comment'>-- | Generates three elements.</span> <a name="line-135"></a> <a name="line-136"></a><a name="three"></a><span class='hs-definition'>three</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Gen</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Gen</span> <span class='hs-layout'>(</span><span class='hs-varid'>a</span><span class='hs-layout'>,</span> <span class='hs-varid'>a</span><span class='hs-layout'>,</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <a name="line-137"></a><span class='hs-definition'>three</span> <span class='hs-varid'>gen</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>liftM3</span> <span class='hs-conid'>(,,)</span> <span class='hs-varid'>gen</span> <span class='hs-varid'>gen</span> <span class='hs-varid'>gen</span> <a name="line-138"></a> <a name="line-139"></a><span class='hs-comment'>------------------------------------------------------------------------</span> <a name="line-140"></a><span class='hs-comment'>-- Test driver</span> <a name="line-141"></a> <a name="line-142"></a><span class='hs-comment'>-- | Runs the tests, and returns 'True' if all tests were successful.</span> <a name="line-143"></a> <a name="line-144"></a><a name="runTests"></a><span class='hs-definition'>runTests</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>String</span> <span class='hs-comment'>-- ^ A label for the tests. Used for</span> <a name="line-145"></a> <span class='hs-comment'>-- informational purposes.</span> <a name="line-146"></a> <span class='hs-keyglyph'>-></span> <span class='hs-keyglyph'>[</span><span class='hs-conid'>IO</span> <span class='hs-conid'>Bool</span><span class='hs-keyglyph'>]</span> <a name="line-147"></a> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>Bool</span> <a name="line-148"></a><span class='hs-definition'>runTests</span> <span class='hs-varid'>name</span> <span class='hs-varid'>tests</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>do</span> <a name="line-149"></a> <span class='hs-varid'>putStrLn</span> <span class='hs-varid'>name</span> <a name="line-150"></a> <span class='hs-varid'>fmap</span> <span class='hs-varid'>and</span> <span class='hs-varop'>$</span> <span class='hs-varid'>sequence</span> <span class='hs-varid'>tests</span> </pre></body> </html>
