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<head><title>and -- conjunction</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="_operators.html" title="">operators</a> > <a href="_and.html" title="conjunction">and</a></div>
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<div><h1>and -- conjunction</h1>
<div class="single"><h2>Description</h2>
<div><tt>t and u</tt> -- returns true if <tt>t</tt> is true and <tt>u</tt> is true.<p/>
If <tt>t</tt> is false, then the code in <tt>u</tt> is not evaluated.</div>
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<div class="single"><h2>See also</h2>
<ul><li><span><a href="_or.html" title="disjunction">or</a> -- disjunction</span></li>
<li><span><a href="_not.html" title="negation">not</a> -- negation</span></li>
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<div class="waystouse"><h2>Ways to use <tt>and</tt> :</h2>
<ul><li><span><tt>Expression and Expression</tt> (missing documentation<!-- tag: (and,Expression,Expression) -->)</span></li>
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<div class="waystouse"><h2>For the programmer</h2>
<p>The object <a href="_and.html" title="conjunction">and</a> is <span>a <a href="___Keyword.html">keyword</a></span>.</p>
<div><div><p>This operator may be used as a binary operator in an expression like <tt>x and y</tt>. The user may install <a href="_binary_spmethods.html" title="">binary methods</a> for handling such expressions with code such as</p>
<pre> X and Y := (x,y) -> ...</pre>
<p>where <tt>X</tt> is the class of <tt>x</tt> and <tt>Y</tt> is the class of <tt>y</tt>.</p>
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