haskellTalk/listFunctions.html at master · WizardOfArc/haskellTalk · GitHub

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    <title>List Functions</title>
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    <h1>List Functions</h1>
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        <th>Function</th>
        <th>Description/use</th>
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        <td><pre>map</pre></td>
        <td style="text-align: left"><pre>
map::(a -> b) -> [a] -> [b]
map func list</pre>creates a new list by applying func to each element in input list </td>
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        <td><pre>fold</pre></td>
        <td style="text-align: left"><pre>
foldr :: Foldable t => (a -> b -> b) -> b -> t a -> b
</pre>Reduces a list to a single value by applying a two argument function to each element and the result of the last application: foldr requires a starting value, foldr1 uses the first element in the list as the starting value</td>
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        <td><pre>:</pre> cons</td>
        <td style="text-align: left"><pre>(:) :: a -> [a] -> [a]</pre> appends element to the head of a list - it's the constructor for the list (constructors can be used for destructuring and pattern matching)</td>
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        <td><pre>++</pre> cons</td>
        <td style="text-align: left"><pre>(++) :: [a] -> [a] -> [a]</pre> joins two lists together</td>
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