I&#39;m someone will offer a much more eloquent answer after me but here&#39;s my shot as a fellow beginner:<div><br></div><div>The type Maybe is defined:</div><div><br></div><div>data Maybe a = Just a | Nothing</div><div>
<br></div><div>It means that a value of type Maybe String can manifest in 1 of 2 values: either Nothing, which typically signifies an error has occurred or a &quot;null&quot; value that you&#39;d see in other programming languages.</div>
<div><br></div><div>Just &quot;foo&quot; is a value that represent a value that is <i>not</i> nothing, such as a successful result from a computation. You can pattern match to get the value out of it:</div><div><br></div>
<div>case somethingThatProducesAMaybe of</div><div>  Just success -&gt; doStuff success</div><div>  Nothing -&gt; error &quot;Oh the humanity!&quot;</div><div><br></div><div>I hope that helps.</div><div>-- <br>Michael Xavier<br>
<a href="http://www.michaelxavier.net">http://www.michaelxavier.net</a><br>
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