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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="_making_spa_spnew_spmethod_spfunction.html" title="">making a new method function</a></div>
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<div><h1>making a new method function</h1>
<div>The function <a href="_method.html" title="make a new method function">method</a> can be used to make new functions which execute different bits of code depending on the types of the arguments presented. Our system depends heavily on such functions.<table class="examples"><tr><td><pre>i1 : f = method()
o1 = f
o1 : MethodFunction</pre>
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We can install a method to be used when <tt>f</tt> is applied to a string as follows.<table class="examples"><tr><td><pre>i2 : f String := s -> s|s;</pre>
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<tr><td><pre>i3 : f ".abcd."
o3 = .abcd..abcd.</pre>
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We can check for the types of up to three arguments, too.<table class="examples"><tr><td><pre>i4 : f(ZZ,String) := (n,s) -> concatenate (n:s);</pre>
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<tr><td><pre>i5 : f(5,".abcd.")
o5 = .abcd..abcd..abcd..abcd..abcd.</pre>
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<div><h3>Menu</h3>
<ul><li><span><a href="_method.html" title="make a new method function">method</a> -- make a new method function</span></li>
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