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<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"/><title>4.5&nbsp;Definitions: define</title><link rel="stylesheet" type="text/css" href="../scribble.css" title="default"/><link rel="stylesheet" type="text/css" href="../racket.css" title="default"/><link rel="stylesheet" type="text/css" href="icons.css" title="default"/><link rel="stylesheet" type="text/css" href="../manual-style.css" title="default"/><link rel="stylesheet" type="text/css" href="../manual-racket.css" title="default"/><link rel="stylesheet" type="text/css" href="../manual-racket.css" title="default"/><link rel="stylesheet" type="text/css" href="../doc-site.css" title="default"/><script type="text/javascript" src="../scribble-common.js"></script><script type="text/javascript" src="../manual-racket.js"></script><script type="text/javascript" src="../manual-racket.js"></script><script type="text/javascript" src="../doc-site.js"></script><script type="text/javascript" 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align="right">4.2&nbsp;</td><td><a href="binding.html" class="tocviewlink" data-pltdoc="x">Identifiers and Binding</a></td></tr><tr><td align="right">4.3&nbsp;</td><td><a href="application.html" class="tocviewlink" data-pltdoc="x">Function Calls (Procedure Applications)</a></td></tr><tr><td align="right">4.4&nbsp;</td><td><a href="lambda.html" class="tocviewlink" data-pltdoc="x">Functions (Procedures):<span class="mywbr"> &nbsp;</span> <span class="RktSym"><span class="RktStxLink">lambda</span></span></a></td></tr><tr><td align="right">4.5&nbsp;</td><td><a href="" class="tocviewselflink" data-pltdoc="x">Definitions:<span class="mywbr"> &nbsp;</span> <span class="RktSym"><span class="RktStxLink">define</span></span></a></td></tr><tr><td align="right">4.6&nbsp;</td><td><a href="let.html" class="tocviewlink" data-pltdoc="x">Local Binding</a></td></tr><tr><td align="right">4.7&nbsp;</td><td><a href="conditionals.html" class="tocviewlink" data-pltdoc="x">Conditionals</a></td></tr><tr><td align="right">4.8&nbsp;</td><td><a href="begin.html" class="tocviewlink" data-pltdoc="x">Sequencing</a></td></tr><tr><td align="right">4.9&nbsp;</td><td><a href="set_.html" class="tocviewlink" data-pltdoc="x">Assignment:<span class="mywbr"> &nbsp;</span> <span class="RktSym"><span class="RktStxLink">set!</span></span></a></td></tr><tr><td align="right">4.10&nbsp;</td><td><a href="quote.html" class="tocviewlink" data-pltdoc="x">Quoting:<span class="mywbr"> &nbsp;</span> <span class="RktSym"><span class="RktStxLink">quote</span></span> and <span class="RktVal">'</span></a></td></tr><tr><td align="right">4.11&nbsp;</td><td><a href="qq.html" class="tocviewlink" data-pltdoc="x">Quasiquoting:<span class="mywbr"> &nbsp;</span> <span class="RktSym"><span class="RktStxLink">quasiquote</span></span> and <span class="RktVal">&lsquo;</span></a></td></tr><tr><td align="right">4.12&nbsp;</td><td><a href="case.html" class="tocviewlink" data-pltdoc="x">Simple Dispatch:<span class="mywbr"> &nbsp;</span> <span class="RktSym"><span class="RktStxLink">case</span></span></a></td></tr><tr><td align="right">4.13&nbsp;</td><td><a href="parameterize.html" class="tocviewlink" data-pltdoc="x">Dynamic Binding:<span class="mywbr"> &nbsp;</span> <span class="RktSym"><span class="RktStxLink">parameterize</span></span></a></td></tr></table></div></div><div class="tocviewlist"><table cellspacing="0" cellpadding="0"><tr><td style="width: 1em;"><a href="javascript:void(0);" title="Expand/Collapse" class="tocviewtoggle" onclick="TocviewToggle(this,&quot;tocview_2&quot;);">&#9658;</a></td><td>4.5&nbsp;</td><td><a href="" class="tocviewselflink" data-pltdoc="x">Definitions:<span class="mywbr"> &nbsp;</span> <span class="RktSym"><span class="RktStxLink">define</span></span></a></td></tr></table><div class="tocviewsublistbottom" style="display: none;" id="tocview_2"><table cellspacing="0" cellpadding="0"><tr><td align="right">4.5.1&nbsp;</td><td><a href="#%28part._.Function_.Shorthand%29" class="tocviewlink" data-pltdoc="x">Function Shorthand</a></td></tr><tr><td align="right">4.5.2&nbsp;</td><td><a href="#%28part._.Curried_.Function_.Shorthand%29" class="tocviewlink" data-pltdoc="x">Curried Function Shorthand</a></td></tr><tr><td align="right">4.5.3&nbsp;</td><td><a href="#%28part._multiple-values%29" class="tocviewlink" data-pltdoc="x">Multiple Values and <span class="RktSym"><span class="RktStxLink">define-<wbr></wbr>values</span></span></a></td></tr><tr><td align="right">4.5.4&nbsp;</td><td><a href="#%28part._intdefs%29" class="tocviewlink" data-pltdoc="x">Internal Definitions</a></td></tr></table></div></div></div><div class="tocsub"><div class="tocsubtitle">On this page:</div><table class="tocsublist" cellspacing="0"><tr><td><span class="tocsublinknumber">4.5.1<tt>&nbsp;</tt></span><a href="#%28part._.Function_.Shorthand%29" class="tocsubseclink" data-pltdoc="x">Function Shorthand</a></td></tr><tr><td><span class="tocsublinknumber">4.5.2<tt>&nbsp;</tt></span><a href="#%28part._.Curried_.Function_.Shorthand%29" class="tocsubseclink" data-pltdoc="x">Curried Function Shorthand</a></td></tr><tr><td><span class="tocsublinknumber">4.5.3<tt>&nbsp;</tt></span><a href="#%28part._multiple-values%29" class="tocsubseclink" data-pltdoc="x">Multiple Values and <span class="RktSym"><span class="RktStxLink">define-<wbr></wbr>values</span></span></a></td></tr><tr><td><span class="tocsublinknumber">4.5.4<tt>&nbsp;</tt></span><a href="#%28part._intdefs%29" class="tocsubseclink" data-pltdoc="x">Internal Definitions</a></td></tr></table></div></div><div class="maincolumn"><div class="main"><div class="navsettop"><span class="navleft"><form class="searchform"><input class="searchbox" style="color: #888;" type="text" value="...search manuals..." title="Enter a search string to search the manuals" onkeypress="return DoSearchKey(event, this, &quot;6.1&quot;, &quot;../&quot;);" onfocus="this.style.color=&quot;black&quot;; this.style.textAlign=&quot;left&quot;; if (this.value == &quot;...search manuals...&quot;) this.value=&quot;&quot;;" onblur="if (this.value.match(/^ *$/)) { this.style.color=&quot;#888&quot;; this.style.textAlign=&quot;center&quot;; this.value=&quot;...search manuals...&quot;; }"/></form>&nbsp;&nbsp;<a href="../index.html" title="up to the documentation top" data-pltdoc="x" onclick="return GotoPLTRoot(&quot;6.1&quot;);">top</a></span><span class="navright">&nbsp;&nbsp;<a href="lambda.html" title="backward to &quot;4.4 Functions (Procedures): lambda&quot;" data-pltdoc="x">&larr; prev</a>&nbsp;&nbsp;<a href="scheme-forms.html" title="up to &quot;4 Expressions and Definitions&quot;" data-pltdoc="x">up</a>&nbsp;&nbsp;<a href="let.html" title="forward to &quot;4.6 Local Binding&quot;" data-pltdoc="x">next &rarr;</a></span>&nbsp;</div><h4 x-source-module="(lib &quot;scribblings/guide/guide.scrbl&quot;)" x-part-tag="&quot;define&quot;">4.5<tt>&nbsp;</tt><a name="(part._define)"></a>Definitions: <span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=define.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._define%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">define</a></span></h4><p>A basic definition has the form</p><blockquote class="leftindent"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=define.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._define%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">define</a></span><span class="hspace">&nbsp;</span><span class="RktVar">id</span><span class="hspace">&nbsp;</span><span class="RktVar">expr</span><span class="RktPn">)</span></td></tr></table></blockquote></blockquote><p>in which case <span class="RktVar">id</span> is bound to the result of
<span class="RktVar">expr</span>.</p><p><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><p>Examples:</p></td></tr><tr><td><blockquote class="SCodeFlow"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=define.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._define%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">define</a></span><span class="hspace">&nbsp;</span><span class="RktSym">salutation</span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=pairs.html%23%2528def._%2528%2528quote._%7E23%7E25kernel%2529._list-ref%2529%2529&amp;version=6.1" class="RktValLink Sq" data-pltdoc="x">list-ref</a></span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">(</span><span class="RktVal">"Hi"</span><span class="hspace">&nbsp;</span><span class="RktVal">"Hello"</span><span class="RktVal">)</span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=generic-numbers.html%23%2528def._%2528%2528quote._%7E23%7E25kernel%2529._random%2529%2529&amp;version=6.1" class="RktValLink Sq" data-pltdoc="x">random</a></span><span class="hspace">&nbsp;</span><span class="RktVal">2</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td> </td></tr></table></td></tr><tr><td><table cellspacing="0" cellpadding="0"><tr><td></td></tr></table></td></tr><tr><td><span class="stt">&gt; </span><span class="RktSym">salutation</span></td></tr><tr><td><p><span class="RktRes">"Hello"</span></p></td></tr></table></blockquote></td></tr></table></p><h5 x-source-module="(lib &quot;scribblings/guide/guide.scrbl&quot;)" x-part-tag="&quot;Function_Shorthand&quot;">4.5.1<tt>&nbsp;</tt><a name="(part._.Function_.Shorthand)"></a>Function Shorthand</h5><p>The <span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=define.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._define%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">define</a></span> form also supports a shorthand for function
definitions:</p><blockquote class="leftindent"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=define.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._define%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">define</a></span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktVar">id</span><span class="hspace">&nbsp;</span><span class="RktVar">arg</span><span class="hspace">&nbsp;</span><span class="RktMeta">...</span><span class="RktPn">)</span><span class="hspace">&nbsp;</span><span class="RktVar">body</span><span class="hspace">&nbsp;</span><span class="RktMeta">...+</span><span class="RktPn">)</span></td></tr></table></blockquote></blockquote><p>which is a shorthand for</p><blockquote class="SCodeFlow"><p><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=define.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._define%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">define</a></span><span class="hspace">&nbsp;</span><span class="RktVar">id</span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=lambda.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._lambda%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">lambda</a></span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktVar">arg</span><span class="hspace">&nbsp;</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=stx-patterns.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fstxcase-scheme..rkt%2529._......%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">...</a></span><span class="RktPn">)</span><span class="hspace">&nbsp;</span><span class="RktVar">body</span><span class="hspace">&nbsp;</span><span class="RktSym">...+</span><span class="RktPn">)</span><span class="RktPn">)</span></p></blockquote><p><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><p>Examples:</p></td></tr><tr><td><blockquote class="SCodeFlow"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=define.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._define%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">define</a></span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym">greet</span><span class="hspace">&nbsp;</span><span class="RktSym">name</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=strings.html%23%2528def._%2528%2528quote._%7E23%7E25kernel%2529._string-append%2529%2529&amp;version=6.1" class="RktValLink Sq" data-pltdoc="x">string-append</a></span><span class="hspace">&nbsp;</span><span class="RktSym">salutation</span><span class="hspace">&nbsp;</span><span class="RktVal">", "</span><span class="hspace">&nbsp;</span><span class="RktSym">name</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td> </td></tr></table></td></tr><tr><td><table cellspacing="0" cellpadding="0"><tr><td></td></tr></table></td></tr><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym">greet</span><span class="hspace">&nbsp;</span><span class="RktVal">"John"</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">"Hello, John"</span></p></td></tr></table></blockquote></td></tr></table></p><blockquote class="SCodeFlow"><table cellspacing="0" cellpadding="0"><tr><td><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=define.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._define%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">define</a></span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym">greet</span><span class="hspace">&nbsp;</span><span class="RktSym">first</span><span class="hspace">&nbsp;</span><span class="RktPn">[</span><span class="RktSym">surname</span><span class="hspace">&nbsp;</span><span class="RktVal">"Smith"</span><span class="RktPn">]</span><span class="hspace">&nbsp;</span><span class="RktPn">#:hi</span><span class="hspace">&nbsp;</span><span class="RktPn">[</span><span class="RktSym">hi</span><span class="hspace">&nbsp;</span><span class="RktSym">salutation</span><span class="RktPn">]</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=strings.html%23%2528def._%2528%2528quote._%7E23%7E25kernel%2529._string-append%2529%2529&amp;version=6.1" class="RktValLink Sq" data-pltdoc="x">string-append</a></span><span class="hspace">&nbsp;</span><span class="RktSym">hi</span><span class="hspace">&nbsp;</span><span class="RktVal">", "</span><span class="hspace">&nbsp;</span><span class="RktSym">first</span><span class="hspace">&nbsp;</span><span class="RktVal">" "</span><span class="hspace">&nbsp;</span><span class="RktSym">surname</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr></table></td></tr><tr><td><p>&nbsp;</p></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym">greet</span><span class="hspace">&nbsp;</span><span class="RktVal">"John"</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">"Hello, John Smith"</span></p></td></tr><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym">greet</span><span class="hspace">&nbsp;</span><span class="RktVal">"John"</span><span class="hspace">&nbsp;</span><span class="RktPn">#:hi</span><span class="hspace">&nbsp;</span><span class="RktVal">"Hey"</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">"Hey, John Smith"</span></p></td></tr><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym">greet</span><span class="hspace">&nbsp;</span><span class="RktVal">"John"</span><span class="hspace">&nbsp;</span><span class="RktVal">"Doe"</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">"Hello, John Doe"</span></p></td></tr></table></td></tr></table></blockquote><p>The function shorthand via <span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=define.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._define%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">define</a></span> also supports a
<a href="lambda.html#%28tech._rest._argument%29" class="techoutside" data-pltdoc="x"><span class="techinside">rest argument</span></a> (i.e., a final argument to collect extra
arguments in a list):</p><blockquote class="leftindent"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=define.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._define%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">define</a></span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktVar">id</span><span class="hspace">&nbsp;</span><span class="RktVar">arg</span><span class="hspace">&nbsp;</span><span class="RktMeta">...</span><span class="hspace">&nbsp;</span><span class="RktPn">. </span><span class="RktVar">rest-id</span><span class="RktPn">)</span><span class="hspace">&nbsp;</span><span class="RktVar">body</span><span class="hspace">&nbsp;</span><span class="RktMeta">...+</span><span class="RktPn">)</span></td></tr></table></blockquote></blockquote><p>which is a shorthand</p><blockquote class="SCodeFlow"><p><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=define.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._define%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">define</a></span><span class="hspace">&nbsp;</span><span class="RktVar">id</span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=lambda.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._lambda%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">lambda</a></span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktVar">arg</span><span class="hspace">&nbsp;</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=stx-patterns.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fstxcase-scheme..rkt%2529._......%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">...</a></span><span class="hspace">&nbsp;</span><span class="RktPn">. </span><span class="RktVar">rest-id</span><span class="RktPn">)</span><span class="hspace">&nbsp;</span><span class="RktVar">body</span><span class="hspace">&nbsp;</span><span class="RktSym">...+</span><span class="RktPn">)</span><span class="RktPn">)</span></p></blockquote><p><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><p>Examples:</p></td></tr><tr><td><blockquote class="SCodeFlow"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=define.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._define%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">define</a></span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym">avg</span><span class="hspace">&nbsp;</span><span class="RktPn">. </span><span class="RktSym">l</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=generic-numbers.html%23%2528def._%2528%2528quote._%7E23%7E25kernel%2529._%252F%2529%2529&amp;version=6.1" class="RktValLink Sq" data-pltdoc="x">/</a></span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=procedures.html%23%2528def._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._apply%2529%2529&amp;version=6.1" class="RktValLink Sq" data-pltdoc="x">apply</a></span><span class="hspace">&nbsp;</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=generic-numbers.html%23%2528def._%2528%2528quote._%7E23%7E25kernel%2529._%252B%2529%2529&amp;version=6.1" class="RktValLink Sq" data-pltdoc="x">+</a></span><span class="hspace">&nbsp;</span><span class="RktSym">l</span><span class="RktPn">)</span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=pairs.html%23%2528def._%2528%2528quote._%7E23%7E25kernel%2529._length%2529%2529&amp;version=6.1" class="RktValLink Sq" data-pltdoc="x">length</a></span><span class="hspace">&nbsp;</span><span class="RktSym">l</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td> </td></tr></table></td></tr><tr><td><table cellspacing="0" cellpadding="0"><tr><td></td></tr></table></td></tr><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym">avg</span><span class="hspace">&nbsp;</span><span class="RktVal">1</span><span class="hspace">&nbsp;</span><span class="RktVal">2</span><span class="hspace">&nbsp;</span><span class="RktVal">3</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">2</span></p></td></tr></table></blockquote></td></tr></table></p><h5 x-source-module="(lib &quot;scribblings/guide/guide.scrbl&quot;)" x-part-tag="&quot;Curried_Function_Shorthand&quot;">4.5.2<tt>&nbsp;</tt><a name="(part._.Curried_.Function_.Shorthand)"></a>Curried Function Shorthand</h5><p>Consider the following <span class="RktSym">make-add-suffix</span> function that takes a
string and returns another function that takes a string:</p><blockquote class="SCodeFlow"><table cellspacing="0" cellpadding="0"><tr><td><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=define.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._define%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">define</a></span><span class="hspace">&nbsp;</span><span class="RktSym">make-add-suffix</span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=lambda.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._lambda%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">lambda</a></span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym">s2</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;&nbsp;&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=lambda.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._lambda%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">lambda</a></span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym">s</span><span class="RktPn">)</span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=strings.html%23%2528def._%2528%2528quote._%7E23%7E25kernel%2529._string-append%2529%2529&amp;version=6.1" class="RktValLink Sq" data-pltdoc="x">string-append</a></span><span class="hspace">&nbsp;</span><span class="RktSym">s</span><span class="hspace">&nbsp;</span><span class="RktSym">s2</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr></table></td></tr><tr><td><p>&nbsp;</p></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td></td></tr></table></td></tr></table></blockquote><p>Although it&rsquo;s not common, result of <span class="RktSym">make-add-suffix</span> could be
called directly, like this:</p><blockquote class="SCodeFlow"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktPn">(</span><span class="RktSym">make-add-suffix</span><span class="hspace">&nbsp;</span><span class="RktVal">"!"</span><span class="RktPn">)</span><span class="hspace">&nbsp;</span><span class="RktVal">"hello"</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">"hello!"</span></p></td></tr></table></blockquote><p>In a sense, <span class="RktSym">make-add-suffix</span> is a function takes two
arguments, but it takes them one at a time. A function that takes some
of its arguments and returns a function to consume more is sometimes
called a <span style="font-style: italic">curried function</span>.</p><p>Using the function-shorthand form of <span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=define.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._define%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">define</a></span>,
<span class="RktSym">make-add-suffix</span> can be written equivalently as</p><blockquote class="SCodeFlow"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=define.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._define%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">define</a></span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym">make-add-suffix</span><span class="hspace">&nbsp;</span><span class="RktSym">s2</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=lambda.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._lambda%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">lambda</a></span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym">s</span><span class="RktPn">)</span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=strings.html%23%2528def._%2528%2528quote._%7E23%7E25kernel%2529._string-append%2529%2529&amp;version=6.1" class="RktValLink Sq" data-pltdoc="x">string-append</a></span><span class="hspace">&nbsp;</span><span class="RktSym">s</span><span class="hspace">&nbsp;</span><span class="RktSym">s2</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr></table></blockquote><p>This shorthand reflects the shape of the function call
<span class="RktPn">(</span><span class="RktSym">make-add-suffix</span><span class="stt"> </span><span class="RktVal">"!"</span><span class="RktPn">)</span>. The <span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=define.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._define%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">define</a></span> form further
supports a shorthand for defining curried functions that reflects
nested function calls:</p><p><div class="SIntrapara"><blockquote class="SCodeFlow"><table cellspacing="0" cellpadding="0"><tr><td><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=define.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._define%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">define</a></span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktPn">(</span><span class="RktSym">make-add-suffix</span><span class="hspace">&nbsp;</span><span class="RktSym">s2</span><span class="RktPn">)</span><span class="hspace">&nbsp;</span><span class="RktSym">s</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=strings.html%23%2528def._%2528%2528quote._%7E23%7E25kernel%2529._string-append%2529%2529&amp;version=6.1" class="RktValLink Sq" data-pltdoc="x">string-append</a></span><span class="hspace">&nbsp;</span><span class="RktSym">s</span><span class="hspace">&nbsp;</span><span class="RktSym">s2</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr></table></td></tr><tr><td><p>&nbsp;</p></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktPn">(</span><span class="RktSym">make-add-suffix</span><span class="hspace">&nbsp;</span><span class="RktVal">"!"</span><span class="RktPn">)</span><span class="hspace">&nbsp;</span><span class="RktVal">"hello"</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">"hello!"</span></p></td></tr></table></td></tr></table></blockquote></div><div class="SIntrapara"><blockquote class="SCodeFlow"><table cellspacing="0" cellpadding="0"><tr><td><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=define.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._define%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">define</a></span><span class="hspace">&nbsp;</span><span class="RktSym">louder</span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym">make-add-suffix</span><span class="hspace">&nbsp;</span><span class="RktVal">"!"</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=define.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._define%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">define</a></span><span class="hspace">&nbsp;</span><span class="RktSym">less-sure</span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym">make-add-suffix</span><span class="hspace">&nbsp;</span><span class="RktVal">"?"</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr></table></td></tr><tr><td><p>&nbsp;</p></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym">less-sure</span><span class="hspace">&nbsp;</span><span class="RktVal">"really"</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">"really?"</span></p></td></tr><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym">louder</span><span class="hspace">&nbsp;</span><span class="RktVal">"really"</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">"really!"</span></p></td></tr></table></td></tr></table></blockquote></div></p><p>The full syntax of the function shorthand for <span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=define.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._define%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">define</a></span> is as follows:</p><blockquote class="leftindent"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=define.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._define%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">define</a></span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktVar">head</span><span class="hspace">&nbsp;</span><span class="RktVar">args</span><span class="RktPn">)</span><span class="hspace">&nbsp;</span><span class="RktVar">body</span><span class="hspace">&nbsp;</span><span class="RktMeta">...+</span><span class="RktPn">)</span></td></tr><tr><td><span class="stt">&nbsp;</span></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="specgrammar"><tr><td align="right" valign="baseline"><span class="RktVar">head</span></td><td align="left" valign="baseline"><span class="stt">&nbsp;</span></td><td align="center" valign="baseline">=</td><td align="left" valign="baseline"><span class="stt">&nbsp;</span></td><td align="left" valign="baseline"><span class="RktVar">id</span></td></tr><tr><td align="right" valign="baseline"><span class="stt">&nbsp;</span></td><td align="left" valign="baseline"><span class="stt">&nbsp;</span></td><td align="center" valign="baseline">|</td><td align="left" valign="baseline"><span class="stt">&nbsp;</span></td><td align="left" valign="baseline"><span class="RktPn">(</span><span class="RktVar">head</span><span class="hspace">&nbsp;</span><span class="RktVar">args</span><span class="RktPn">)</span></td></tr><tr><td align="right" valign="baseline"><span class="stt">&nbsp;</span></td><td align="left" valign="baseline"><span class="stt">&nbsp;</span></td><td align="center" valign="baseline"><span class="stt">&nbsp;</span></td><td align="left" valign="baseline"><span class="stt">&nbsp;</span></td><td align="left" valign="baseline"><span class="stt">&nbsp;</span></td></tr><tr><td align="right" valign="baseline"><span class="RktVar">args</span></td><td align="left" valign="baseline"><span class="stt">&nbsp;</span></td><td align="center" valign="baseline">=</td><td align="left" valign="baseline"><span class="stt">&nbsp;</span></td><td align="left" valign="baseline"><span class="RktVar">arg</span><span class="hspace">&nbsp;</span><span class="RktMeta">...</span></td></tr><tr><td align="right" valign="baseline"><span class="stt">&nbsp;</span></td><td align="left" valign="baseline"><span class="stt">&nbsp;</span></td><td align="center" valign="baseline">|</td><td align="left" valign="baseline"><span class="stt">&nbsp;</span></td><td align="left" valign="baseline"><span class="RktVar">arg</span><span class="hspace">&nbsp;</span><span class="RktMeta">...</span><span class="hspace">&nbsp;</span><span class="RktPn">.</span><span class="hspace">&nbsp;</span><span class="RktVar">rest-id</span></td></tr></table></td></tr></table></blockquote></blockquote><p>The expansion of this shorthand has one nested <span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=lambda.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._lambda%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">lambda</a></span> form
for each <span class="RktVar">head</span> in the definition, where the innermost
<span class="RktVar">head</span> corresponds to the outermost <span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=lambda.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._lambda%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">lambda</a></span>.</p><h5 x-source-module="(lib &quot;scribblings/guide/guide.scrbl&quot;)" x-part-tag="&quot;multiple-values&quot;">4.5.3<tt>&nbsp;</tt><a name="(part._multiple-values)"></a>Multiple Values and <span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=define.html%23%2528form._%2528%2528quote._%7E23%7E25kernel%2529._define-values%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">define-values</a></span></h5><p>A Racket expression normally produces a single result, but some
expressions can produce multiple results. For example,
<span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=generic-numbers.html%23%2528def._%2528%2528quote._%7E23%7E25kernel%2529._quotient%2529%2529&amp;version=6.1" class="RktValLink Sq" data-pltdoc="x">quotient</a></span> and <span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=generic-numbers.html%23%2528def._%2528%2528quote._%7E23%7E25kernel%2529._remainder%2529%2529&amp;version=6.1" class="RktValLink Sq" data-pltdoc="x">remainder</a></span> each produce a single value,
but <span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=generic-numbers.html%23%2528def._%2528%2528quote._%7E23%7E25kernel%2529._quotient%252Fremainder%2529%2529&amp;version=6.1" class="RktValLink Sq" data-pltdoc="x">quotient/remainder</a></span> produces the same two values at once:</p><blockquote class="SCodeFlow"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=generic-numbers.html%23%2528def._%2528%2528quote._%7E23%7E25kernel%2529._quotient%2529%2529&amp;version=6.1" class="RktValLink Sq" data-pltdoc="x">quotient</a></span><span class="hspace">&nbsp;</span><span class="RktVal">13</span><span class="hspace">&nbsp;</span><span class="RktVal">3</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">4</span></p></td></tr><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=generic-numbers.html%23%2528def._%2528%2528quote._%7E23%7E25kernel%2529._remainder%2529%2529&amp;version=6.1" class="RktValLink Sq" data-pltdoc="x">remainder</a></span><span class="hspace">&nbsp;</span><span class="RktVal">13</span><span class="hspace">&nbsp;</span><span class="RktVal">3</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">1</span></p></td></tr><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=generic-numbers.html%23%2528def._%2528%2528quote._%7E23%7E25kernel%2529._quotient%252Fremainder%2529%2529&amp;version=6.1" class="RktValLink Sq" data-pltdoc="x">quotient/remainder</a></span><span class="hspace">&nbsp;</span><span class="RktVal">13</span><span class="hspace">&nbsp;</span><span class="RktVal">3</span><span class="RktPn">)</span></td></tr><tr><td><table cellspacing="0" cellpadding="0"><tr><td><p><span class="RktRes">4</span></p></td></tr><tr><td><p><span class="RktRes">1</span></p></td></tr></table></td></tr></table></blockquote><p>As shown above, the <a href="intro.html#%28tech._repl%29" class="techoutside" data-pltdoc="x"><span class="techinside">REPL</span></a> prints each result value on its own
line.</p><p>Multiple-valued functions can be implemented in terms of the
<span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=values.html%23%2528def._%2528%2528quote._%7E23%7E25kernel%2529._values%2529%2529&amp;version=6.1" class="RktValLink Sq" data-pltdoc="x">values</a></span> function, which takes any number of values and
returns them as the results:</p><p><div class="SIntrapara"><blockquote class="SCodeFlow"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=values.html%23%2528def._%2528%2528quote._%7E23%7E25kernel%2529._values%2529%2529&amp;version=6.1" class="RktValLink Sq" data-pltdoc="x">values</a></span><span class="hspace">&nbsp;</span><span class="RktVal">1</span><span class="hspace">&nbsp;</span><span class="RktVal">2</span><span class="hspace">&nbsp;</span><span class="RktVal">3</span><span class="RktPn">)</span></td></tr><tr><td><table cellspacing="0" cellpadding="0"><tr><td><p><span class="RktRes">1</span></p></td></tr><tr><td><p><span class="RktRes">2</span></p></td></tr><tr><td><p><span class="RktRes">3</span></p></td></tr></table></td></tr></table></blockquote></div><div class="SIntrapara"><blockquote class="SCodeFlow"><table cellspacing="0" cellpadding="0"><tr><td><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=define.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._define%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">define</a></span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym">split-name</span><span class="hspace">&nbsp;</span><span class="RktSym">name</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=let.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fletstx-scheme..rkt%2529._let%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">let</a></span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktPn">[</span><span class="RktSym">parts</span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=regexp.html%23%2528def._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._regexp-split%2529%2529&amp;version=6.1" class="RktValLink Sq" data-pltdoc="x">regexp-split</a></span><span class="hspace">&nbsp;</span><span class="RktVal">" "</span><span class="hspace">&nbsp;</span><span class="RktSym">name</span><span class="RktPn">)</span><span class="RktPn">]</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;&nbsp;&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=if.html%23%2528form._%2528%2528quote._%7E23%7E25kernel%2529._if%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">if</a></span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=generic-numbers.html%23%2528def._%2528%2528quote._%7E23%7E25kernel%2529._%7E3d%2529%2529&amp;version=6.1" class="RktValLink Sq" data-pltdoc="x">=</a></span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=pairs.html%23%2528def._%2528%2528quote._%7E23%7E25kernel%2529._length%2529%2529&amp;version=6.1" class="RktValLink Sq" data-pltdoc="x">length</a></span><span class="hspace">&nbsp;</span><span class="RktSym">parts</span><span class="RktPn">)</span><span class="hspace">&nbsp;</span><span class="RktVal">2</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=values.html%23%2528def._%2528%2528quote._%7E23%7E25kernel%2529._values%2529%2529&amp;version=6.1" class="RktValLink Sq" data-pltdoc="x">values</a></span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=pairs.html%23%2528def._%2528%2528quote._%7E23%7E25kernel%2529._list-ref%2529%2529&amp;version=6.1" class="RktValLink Sq" data-pltdoc="x">list-ref</a></span><span class="hspace">&nbsp;</span><span class="RktSym">parts</span><span class="hspace">&nbsp;</span><span class="RktVal">0</span><span class="RktPn">)</span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=pairs.html%23%2528def._%2528%2528quote._%7E23%7E25kernel%2529._list-ref%2529%2529&amp;version=6.1" class="RktValLink Sq" data-pltdoc="x">list-ref</a></span><span class="hspace">&nbsp;</span><span class="RktSym">parts</span><span class="hspace">&nbsp;</span><span class="RktVal">1</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=exns.html%23%2528def._%2528%2528quote._%7E23%7E25kernel%2529._error%2529%2529&amp;version=6.1" class="RktValLink Sq" data-pltdoc="x">error</a></span><span class="hspace">&nbsp;</span><span class="RktVal">"not a &lt;first&gt; &lt;last&gt; name"</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr></table></td></tr><tr><td><p>&nbsp;</p></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym">split-name</span><span class="hspace">&nbsp;</span><span class="RktVal">"Adam Smith"</span><span class="RktPn">)</span></td></tr><tr><td><table cellspacing="0" cellpadding="0"><tr><td><p><span class="RktRes">"Adam"</span></p></td></tr><tr><td><p><span class="RktRes">"Smith"</span></p></td></tr></table></td></tr></table></td></tr></table></blockquote></div></p><p>The <span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=define.html%23%2528form._%2528%2528quote._%7E23%7E25kernel%2529._define-values%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">define-values</a></span> form binds multiple identifiers at once to
multiple results produced from a single expression:</p><blockquote class="leftindent"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=define.html%23%2528form._%2528%2528quote._%7E23%7E25kernel%2529._define-values%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">define-values</a></span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktVar">id</span><span class="hspace">&nbsp;</span><span class="RktMeta">...</span><span class="RktPn">)</span><span class="hspace">&nbsp;</span><span class="RktVar">expr</span><span class="RktPn">)</span></td></tr></table></blockquote></blockquote><p>The number of results produced by the <span class="RktVar">expr</span> must match the
number of <span class="RktVar">id</span>s.</p><p><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><p>Examples:</p></td></tr><tr><td><blockquote class="SCodeFlow"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=define.html%23%2528form._%2528%2528quote._%7E23%7E25kernel%2529._define-values%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">define-values</a></span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym">given</span><span class="hspace">&nbsp;</span><span class="RktSym">surname</span><span class="RktPn">)</span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym">split-name</span><span class="hspace">&nbsp;</span><span class="RktVal">"Adam Smith"</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td> </td></tr></table></td></tr><tr><td><table cellspacing="0" cellpadding="0"><tr><td></td></tr></table></td></tr><tr><td><span class="stt">&gt; </span><span class="RktSym">given</span></td></tr><tr><td><p><span class="RktRes">"Adam"</span></p></td></tr><tr><td><span class="stt">&gt; </span><span class="RktSym">surname</span></td></tr><tr><td><p><span class="RktRes">"Smith"</span></p></td></tr></table></blockquote></td></tr></table></p><p>A <span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=define.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._define%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">define</a></span> form (that is not a function shorthand) is
equivalent to a <span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=define.html%23%2528form._%2528%2528quote._%7E23%7E25kernel%2529._define-values%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">define-values</a></span> form with a single <span class="RktVar">id</span>.</p><blockquote class="refpara"><blockquote class="refcolumn"><blockquote class="refcontent"><p><span class="imageleft"><img src="magnify.png" alt="+" width="24" height="24"/></span><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=define.html&amp;version=6.1" class="Sq" data-pltdoc="x">Definitions: <span class="RktSym"><span class="RktStxLink">define</span></span>, <span class="RktSym"><span class="RktStxLink">define-syntax</span></span>, ...</a> in <a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=index.html&amp;version=6.1" class="Sq" data-pltdoc="x"><span style="font-weight: bold">The Racket Reference</span></a> provides more on definitions.</p></blockquote></blockquote></blockquote><h5 x-source-module="(lib &quot;scribblings/guide/guide.scrbl&quot;)" x-part-tag="&quot;intdefs&quot;">4.5.4<tt>&nbsp;</tt><a name="(part._intdefs)"></a>Internal Definitions</h5><p>When the grammar for a syntactic form specifies <span class="RktVar">body</span>, then
the corresponding form can be either a definition or an expression.
A definition as a <span class="RktVar">body</span> is an <span style="font-style: italic">internal definition</span>.</p><p>Expressions and internal definitions in a <span class="RktVar">body</span> sequence can
be mixed, as long as the last <span class="RktVar">body</span> is an expression.</p><p>For example, the syntax of <span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=lambda.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._lambda%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">lambda</a></span> is</p><blockquote class="leftindent"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=lambda.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._lambda%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">lambda</a></span><span class="hspace">&nbsp;</span><span class="RktVar">gen-formals</span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktVar">body</span><span class="hspace">&nbsp;</span><span class="RktMeta">...+</span><span class="RktPn">)</span></td></tr></table></td></tr></table></blockquote></blockquote><p>so the following are valid instances of the grammar:</p><blockquote class="SCodeFlow"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=lambda.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._lambda%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">lambda</a></span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym">f</span><span class="RktPn">)</span><span class="hspace">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</span><span class="RktCmt">;</span><span class="RktCmt">&nbsp;</span><span class="RktCmt">no definitions</span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=Writing.html%23%2528def._%2528%2528quote._%7E23%7E25kernel%2529._printf%2529%2529&amp;version=6.1" class="RktValLink Sq" data-pltdoc="x">printf</a></span><span class="hspace">&nbsp;</span><span class="RktVal">"running\n"</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktPn">(</span><span class="RktSym">f</span><span class="hspace">&nbsp;</span><span class="RktVal">0</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace">&nbsp;</span></td></tr><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=lambda.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._lambda%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">lambda</a></span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym">f</span><span class="RktPn">)</span><span class="hspace">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</span><span class="RktCmt">;</span><span class="RktCmt">&nbsp;</span><span class="RktCmt">one definition</span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=define.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._define%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">define</a></span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym">log-it</span><span class="hspace">&nbsp;</span><span class="RktSym">what</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;&nbsp;&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=Writing.html%23%2528def._%2528%2528quote._%7E23%7E25kernel%2529._printf%2529%2529&amp;version=6.1" class="RktValLink Sq" data-pltdoc="x">printf</a></span><span class="hspace">&nbsp;</span><span class="RktVal">"~a\n"</span><span class="hspace">&nbsp;</span><span class="RktSym">what</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktPn">(</span><span class="RktSym">log-it</span><span class="hspace">&nbsp;</span><span class="RktVal">"running"</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktPn">(</span><span class="RktSym">f</span><span class="hspace">&nbsp;</span><span class="RktVal">0</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktPn">(</span><span class="RktSym">log-it</span><span class="hspace">&nbsp;</span><span class="RktVal">"done"</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace">&nbsp;</span></td></tr><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=lambda.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._lambda%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">lambda</a></span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym">f</span><span class="hspace">&nbsp;</span><span class="RktSym">n</span><span class="RktPn">)</span><span class="hspace">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</span><span class="RktCmt">;</span><span class="RktCmt">&nbsp;</span><span class="RktCmt">two definitions</span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=define.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._define%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">define</a></span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym">call</span><span class="hspace">&nbsp;</span><span class="RktSym">n</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;&nbsp;&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=if.html%23%2528form._%2528%2528quote._%7E23%7E25kernel%2529._if%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">if</a></span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=number-types.html%23%2528def._%2528%2528quote._%7E23%7E25kernel%2529._zero%7E3f%2529%2529&amp;version=6.1" class="RktValLink Sq" data-pltdoc="x">zero?</a></span><span class="hspace">&nbsp;</span><span class="RktSym">n</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</span><span class="RktPn">(</span><span class="RktSym">log-it</span><span class="hspace">&nbsp;</span><span class="RktVal">"done"</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=begin.html%23%2528form._%2528%2528quote._%7E23%7E25kernel%2529._begin%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">begin</a></span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</span><span class="RktPn">(</span><span class="RktSym">log-it</span><span class="hspace">&nbsp;</span><span class="RktVal">"running"</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</span><span class="RktPn">(</span><span class="RktSym">f</span><span class="hspace">&nbsp;</span><span class="RktSym">n</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</span><span class="RktPn">(</span><span class="RktSym">call</span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=generic-numbers.html%23%2528def._%2528%2528quote._%7E23%7E25kernel%2529._-%2529%2529&amp;version=6.1" class="RktValLink Sq" data-pltdoc="x"><span class="nobreak">-</span></a></span><span class="hspace">&nbsp;</span><span class="RktSym">n</span><span class="hspace">&nbsp;</span><span class="RktVal">1</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=define.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._define%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">define</a></span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym">log-it</span><span class="hspace">&nbsp;</span><span class="RktSym">what</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;&nbsp;&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=Writing.html%23%2528def._%2528%2528quote._%7E23%7E25kernel%2529._printf%2529%2529&amp;version=6.1" class="RktValLink Sq" data-pltdoc="x">printf</a></span><span class="hspace">&nbsp;</span><span class="RktVal">"~a\n"</span><span class="hspace">&nbsp;</span><span class="RktSym">what</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktPn">(</span><span class="RktSym">call</span><span class="hspace">&nbsp;</span><span class="RktSym">n</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr></table></blockquote><p>Internal definitions in a particular <span class="RktVar">body</span> sequence are
mutually recursive; that is, any definition can refer to any other
definition&#8212;<wbr></wbr>as long as the reference isn&rsquo;t actually evaluated before
its definition takes place. If a definition is referenced too early,
an error occurs.</p><p><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><p>Examples:</p></td></tr><tr><td><blockquote class="SCodeFlow"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=define.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._define%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">define</a></span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym">weird</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=define.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._define%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">define</a></span><span class="hspace">&nbsp;</span><span class="RktSym">x</span><span class="hspace">&nbsp;</span><span class="RktSym">x</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktSym">x</span><span class="RktPn">)</span></td></tr><tr><td> </td></tr></table></td></tr><tr><td><table cellspacing="0" cellpadding="0"><tr><td></td></tr></table></td></tr><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym">weird</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktErr">x: undefined;</span></p></td></tr><tr><td><p><span class="RktErr"></span><span class="hspace">&nbsp;</span><span class="RktErr">cannot use before initialization</span></p></td></tr></table></blockquote></td></tr></table></p><p>A sequence of internal definitions using just <span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=define.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._define%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">define</a></span> is
easily translated to an equivalent <span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=let.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fletstx-scheme..rkt%2529._letrec%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">letrec</a></span> form (as introduced
in the next section). However, other definition forms can appear as a
<span class="RktVar">body</span>, including <span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=define.html%23%2528form._%2528%2528quote._%7E23%7E25kernel%2529._define-values%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">define-values</a></span>, <span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=define-struct.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._struct%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">struct</a></span> (see
<a href="define-struct.html" data-pltdoc="x">Programmer-Defined Datatypes</a>) or <span class="RktSym"><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=define.html%23%2528form._%2528%2528lib._racket%252Fprivate%252Fbase..rkt%2529._define-syntax%2529%2529&amp;version=6.1" class="RktStxLink Sq" data-pltdoc="x">define-syntax</a></span> (see
<a href="macros.html" data-pltdoc="x">Macros</a>).</p><blockquote class="refpara"><blockquote class="refcolumn"><blockquote class="refcontent"><p><span class="imageleft"><img src="magnify.png" alt="+" width="24" height="24"/></span><a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=syntax-model.html%23%2528part._intdef-body%2529&amp;version=6.1" class="Sq" data-pltdoc="x">Internal Definitions</a> in <a href="http://download.racket-lang.org/docs/6.1/html/local-redirect/index.html?doc=reference&amp;rel=index.html&amp;version=6.1" class="Sq" data-pltdoc="x"><span style="font-weight: bold">The Racket Reference</span></a> documents the fine points of internal definitions.</p></blockquote></blockquote></blockquote><div class="navsetbottom"><span class="navleft"><form class="searchform"><input class="searchbox" style="color: #888;" type="text" value="...search manuals..." title="Enter a search string to search the manuals" onkeypress="return DoSearchKey(event, this, &quot;6.1&quot;, &quot;../&quot;);" onfocus="this.style.color=&quot;black&quot;; this.style.textAlign=&quot;left&quot;; if (this.value == &quot;...search manuals...&quot;) this.value=&quot;&quot;;" onblur="if (this.value.match(/^ *$/)) { this.style.color=&quot;#888&quot;; this.style.textAlign=&quot;center&quot;; this.value=&quot;...search manuals...&quot;; }"/></form>&nbsp;&nbsp;<a href="../index.html" title="up to the documentation top" data-pltdoc="x" onclick="return GotoPLTRoot(&quot;6.1&quot;);">top</a></span><span class="navright">&nbsp;&nbsp;<a href="lambda.html" title="backward to &quot;4.4 Functions (Procedures): lambda&quot;" data-pltdoc="x">&larr; prev</a>&nbsp;&nbsp;<a href="scheme-forms.html" title="up to &quot;4 Expressions and Definitions&quot;" data-pltdoc="x">up</a>&nbsp;&nbsp;<a href="let.html" title="forward to &quot;4.6 Local Binding&quot;" data-pltdoc="x">next &rarr;</a></span>&nbsp;</div></div></div><div id="contextindicator">&nbsp;</div></body></html>