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<head><title>instance -- whether something has a certain type</title>
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<div><a href="index.html" title="">Macaulay2Doc</a> > <a href="___The_sp__Macaulay2_splanguage.html" title="">The Macaulay2 language</a> > <a href="_what_spa_spclass_spis.html" title="">what a class is</a> > <a href="_instance.html" title="whether something has a certain type">instance</a></div>
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<div><h1>instance -- whether something has a certain type</h1>
<div class="single"><h2>Description</h2>
<div><tt>instance(x,X)</tt> -- tells whether <tt>x</tt> is an instance of the type <tt>X</tt>.<p/>
We say that x is an instance of X if X is the class of x, or a parent of the class of x, or a grandparent, and so on.<p/>
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<div class="single"><h2>See also</h2>
<ul><li><span><a href="_class.html" title="class of an object">class</a> -- class of an object</span></li>
<li><span><a href="_parent.html" title="parent type of an object">parent</a> -- parent type of an object</span></li>
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<div class="waystouse"><h2>Ways to use <tt>instance</tt> :</h2>
<ul><li>instance(Thing,Type)</li>
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