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<head><title>Set - Set -- set difference</title>
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<div><h1>Set - Set -- set difference</h1>
<div class="single"><h2>Synopsis</h2>
<ul><li><div class="list"><dl class="element"><dt class="heading">Usage: </dt><dd class="value"><div><tt>x - y</tt></div>
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<li><span>Operator: <a href="_-.html" title="a unary or binary operator, usually used for negation or subtraction">-</a></span></li>
<li><div class="single">Inputs:<ul><li><span><tt>x</tt>, <span>a <a href="___Set.html">set</a></span>, or <span>a <a href="___List.html">list</a></span></span></li>
<li><span><tt>y</tt>, <span>a <a href="___Set.html">set</a></span>, or <span>a <a href="___List.html">list</a></span></span></li>
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<li><div class="single">Outputs:<ul><li><span><span>a <a href="___Set.html">set</a></span>, or <span>a <a href="___List.html">list</a></span>, consisting of those elements of x not in y</span></li>
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<div class="single"><h2>Description</h2>
<div>At least one of <tt>x</tt>, <tt>y</tt> must be a set, and the other may be a list. If <tt>x</tt> is a list, then so is the result.<table class="examples"><tr><td><pre>i1 : set{a,b,c} - set{a}
o1 = set {b, c}
o1 : Set</pre>
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<tr><td><pre>i2 : set{a,b,c} - {a}
o2 = set {b, c}
o2 : Set</pre>
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<tr><td><pre>i3 : {a,b,c} - set{a}
o3 = {b, c}
o3 : List</pre>
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<div class="single"><h2>See also</h2>
<ul><li><span><a href="___Set.html" title="the class of all sets">Set</a> -- the class of all sets</span></li>
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