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<head><title>return -- return from a function</title>
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<div><h1>return -- return from a function</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>return x</tt></div>
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<li><div class="single">Inputs:<ul><li><span><tt>x</tt>, If <tt>x</tt> is omitted, then <a href="_null.html" title="the unique member of the empty class">null</a> is used.</span></li>
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<li><div class="single">Consequences:<ul><li>Returns <tt>x</tt> as the value of the function currently being evaluated.</li>
<li>Alternatively, as a debugger command, returns <tt>x</tt> as the value of the current expression and stops execution at the next possible point, entering the debugger again.</li>
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<div class="single"><h2>Description</h2>
<div><table class="examples"><tr><td><pre>i1 : f = x -> (
if x == 3 then return;
if x > 3 then return x^2;
5);</pre>
</td></tr>
<tr><td><pre>i2 : f 2
o2 = 5</pre>
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<tr><td><pre>i3 : f 3</pre>
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<tr><td><pre>i4 : f 4
o4 = 16</pre>
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<p>Here is an example of the use of <a href="_return.html" title="return from a function">return</a> as a debugger command.</p>
<table class="examples"><tr><td><pre>i5 : load "Macaulay2Doc/demo1.m2"</pre>
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<tr><td><pre>i6 : code g
o6 = /builddir/build/BUILD/Macaulay2-1.3.1-r10737/Macaulay2/packages/Macaulay2Doc/demo1.m2:11:7-14:8: --source code:
g = y -> (
c := f(y-1);
d := f(y-2);
c+d)</pre>
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<tr><td><pre>i7 : g 2
/builddir/build/BUILD/Macaulay2-1.3.1-r10737/Macaulay2/packages/Macaulay2Doc/demo1.m2:8:12:(3):[2]: error: division by zero
/builddir/build/BUILD/Macaulay2-1.3.1-r10737/Macaulay2/packages/Macaulay2Doc/demo1.m2:8:12:(3):[2]: --entering debugger (type help to see debugger commands)
/builddir/build/BUILD/Macaulay2-1.3.1-r10737/Macaulay2/packages/Macaulay2Doc/demo1.m2:8:11-8:13: --source code:
b := 1/x;</pre>
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<tr><td><pre>ii8 : code f
oo8 = /builddir/build/BUILD/Macaulay2-1.3.1-r10737/Macaulay2/packages/Macaulay2Doc/demo1.m2:6:8-9:8: --source code:
f := x -> (
a := "hi there";
b := 1/x;
b+1)</pre>
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<tr><td><pre>ii9 : return 1/11
/builddir/build/BUILD/Macaulay2-1.3.1-r10737/Macaulay2/packages/Macaulay2Doc/demo1.m2:9:7:(3):[2]: --stepping limit reached
/builddir/build/BUILD/Macaulay2-1.3.1-r10737/Macaulay2/packages/Macaulay2Doc/demo1.m2:9:7:(3):[2]: --entering debugger (type help to see debugger commands)
/builddir/build/BUILD/Macaulay2-1.3.1-r10737/Macaulay2/packages/Macaulay2Doc/demo1.m2:9:6-9:8: --source code:
b+1)</pre>
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<tr><td><pre>ii10 : continue
34
o10 = --
11
o10 : QQ</pre>
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<div class="single"><h2>See also</h2>
<ul><li><span><a href="_break.html" title="break from a loop">break</a> -- break from a loop</span></li>
</ul>
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<div class="waystouse"><h2>For the programmer</h2>
<p>The object <a href="_return.html" title="return from a function">return</a> is <span>a <a href="___Keyword.html">keyword</a></span>.</p>
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