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<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"/><meta name="viewport" content="width=device-width, initial-scale=0.8"/><title>4.9 Keywords</title><link rel="stylesheet" type="text/css" href="../scribble.css" title="default"/><link rel="stylesheet" type="text/css" href="extras.css" title="default"/><link rel="stylesheet" type="text/css" href="icons.css" title="default"/><link rel="stylesheet" type="text/css" href="../racket.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" src="../local-redirect/local-redirect.js"></script><script type="text/javascript" src="../local-redirect/local-user-redirect.js"></script><!--[if IE 6]><style type="text/css">.SIEHidden { overflow: hidden; }</style><![endif]--></head><body id="doc-racket-lang-org"><div class="tocset"><div class="tocview"><div class="tocviewlist tocviewlisttopspace"><div class="tocviewtitle"><table cellspacing="0" cellpadding="0"><tr><td style="width: 1em;"><a href="javascript:void(0);" title="Expand/Collapse" class="tocviewtoggle" onclick="TocviewToggle(this,"tocview_0");">►</a></td><td></td><td><a href="index.html" class="tocviewlink" data-pltdoc="x">The Racket Reference</a></td></tr></table></div><div class="tocviewsublisttop" style="display: none;" id="tocview_0"><table cellspacing="0" cellpadding="0"><tr><td align="right">1 </td><td><a href="model.html" class="tocviewlink" data-pltdoc="x">Language Model</a></td></tr><tr><td align="right">2 </td><td><a href="notation.html" class="tocviewlink" data-pltdoc="x">Notation for Documentation</a></td></tr><tr><td align="right">3 </td><td><a href="syntax.html" class="tocviewlink" data-pltdoc="x">Syntactic Forms</a></td></tr><tr><td align="right">4 </td><td><a href="data.html" class="tocviewselflink" data-pltdoc="x">Datatypes</a></td></tr><tr><td align="right">5 </td><td><a href="structures.html" class="tocviewlink" data-pltdoc="x">Structures</a></td></tr><tr><td align="right">6 </td><td><a href="mzlib_class.html" class="tocviewlink" data-pltdoc="x">Classes and Objects</a></td></tr><tr><td align="right">7 </td><td><a href="mzlib_unit.html" class="tocviewlink" data-pltdoc="x">Units</a></td></tr><tr><td align="right">8 </td><td><a href="contracts.html" class="tocviewlink" data-pltdoc="x">Contracts</a></td></tr><tr><td align="right">9 </td><td><a href="match.html" class="tocviewlink" data-pltdoc="x">Pattern Matching</a></td></tr><tr><td align="right">10 </td><td><a href="control.html" class="tocviewlink" data-pltdoc="x">Control Flow</a></td></tr><tr><td align="right">11 </td><td><a href="concurrency.html" class="tocviewlink" data-pltdoc="x">Concurrency and Parallelism</a></td></tr><tr><td align="right">12 </td><td><a href="Macros.html" class="tocviewlink" data-pltdoc="x">Macros</a></td></tr><tr><td align="right">13 </td><td><a href="input-and-output.html" class="tocviewlink" data-pltdoc="x">Input and Output</a></td></tr><tr><td align="right">14 </td><td><a href="security.html" class="tocviewlink" data-pltdoc="x">Reflection and Security</a></td></tr><tr><td align="right">15 </td><td><a href="os.html" class="tocviewlink" data-pltdoc="x">Operating System</a></td></tr><tr><td align="right">16 </td><td><a href="memory.html" class="tocviewlink" data-pltdoc="x">Memory Management</a></td></tr><tr><td align="right">17 </td><td><a href="unsafe.html" class="tocviewlink" data-pltdoc="x">Unsafe Operations</a></td></tr><tr><td align="right">18 </td><td><a href="running.html" class="tocviewlink" data-pltdoc="x">Running Racket</a></td></tr><tr><td align="right"></td><td><a href="doc-bibliography.html" class="tocviewlink" data-pltdoc="x">Bibliography</a></td></tr><tr><td align="right"></td><td><a href="doc-index.html" class="tocviewlink" data-pltdoc="x">Index</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,"tocview_1");">▼</a></td><td>4 </td><td><a href="data.html" class="tocviewlink" data-pltdoc="x">Datatypes</a></td></tr></table><div class="tocviewsublist" style="display: block;" id="tocview_1"><table cellspacing="0" cellpadding="0"><tr><td align="right">4.1 </td><td><a href="Equality.html" class="tocviewlink" data-pltdoc="x">Equality</a></td></tr><tr><td align="right">4.2 </td><td><a href="booleans.html" class="tocviewlink" data-pltdoc="x">Booleans</a></td></tr><tr><td align="right">4.3 </td><td><a href="numbers.html" class="tocviewlink" data-pltdoc="x">Numbers</a></td></tr><tr><td align="right">4.4 </td><td><a href="strings.html" class="tocviewlink" data-pltdoc="x">Strings</a></td></tr><tr><td align="right">4.5 </td><td><a href="bytestrings.html" class="tocviewlink" data-pltdoc="x">Byte Strings</a></td></tr><tr><td align="right">4.6 </td><td><a href="characters.html" class="tocviewlink" data-pltdoc="x">Characters</a></td></tr><tr><td align="right">4.7 </td><td><a href="symbols.html" class="tocviewlink" data-pltdoc="x">Symbols</a></td></tr><tr><td align="right">4.8 </td><td><a href="regexp.html" class="tocviewlink" data-pltdoc="x">Regular Expressions</a></td></tr><tr><td align="right">4.9 </td><td><a href="keywords.html" class="tocviewselflink" data-pltdoc="x">Keywords</a></td></tr><tr><td align="right">4.10 </td><td><a href="pairs.html" class="tocviewlink" data-pltdoc="x">Pairs and Lists</a></td></tr><tr><td align="right">4.11 </td><td><a href="mpairs.html" class="tocviewlink" data-pltdoc="x">Mutable Pairs and Lists</a></td></tr><tr><td align="right">4.12 </td><td><a href="vectors.html" class="tocviewlink" data-pltdoc="x">Vectors</a></td></tr><tr><td align="right">4.13 </td><td><a href="stencil_vectors.html" class="tocviewlink" data-pltdoc="x">Stencil Vectors</a></td></tr><tr><td align="right">4.14 </td><td><a href="boxes.html" class="tocviewlink" data-pltdoc="x">Boxes</a></td></tr><tr><td align="right">4.15 </td><td><a href="hashtables.html" class="tocviewlink" data-pltdoc="x">Hash Tables</a></td></tr><tr><td align="right">4.16 </td><td><a href="sequences_streams.html" class="tocviewlink" data-pltdoc="x">Sequences and Streams</a></td></tr><tr><td align="right">4.17 </td><td><a href="dicts.html" class="tocviewlink" data-pltdoc="x">Dictionaries</a></td></tr><tr><td align="right">4.18 </td><td><a href="sets.html" class="tocviewlink" data-pltdoc="x">Sets</a></td></tr><tr><td align="right">4.19 </td><td><a href="procedures.html" class="tocviewlink" data-pltdoc="x">Procedures</a></td></tr><tr><td align="right">4.20 </td><td><a href="void.html" class="tocviewlink" data-pltdoc="x">Void</a></td></tr><tr><td align="right">4.21 </td><td><a href="undefined.html" class="tocviewlink" data-pltdoc="x">Undefined</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,"tocview_2");">►</a></td><td>4.9 </td><td><a href="keywords.html" class="tocviewselflink" data-pltdoc="x">Keywords</a></td></tr></table><div class="tocviewsublistbottom" style="display: none;" id="tocview_2"><table cellspacing="0" cellpadding="0"><tr><td align="right">4.9.1 </td><td><a href="keywords.html#%28part._.Additional_.Keyword_.Functions%29" class="tocviewlink" data-pltdoc="x">Additional Keyword Functions</a></td></tr></table></div></div></div><div class="tocsub"><div class="tocsubtitle">On this page:</div><table class="tocsublist" cellspacing="0"><tr><td><a href="keywords.html#%28def._%28%28quote._~23~25kernel%29._keyword~3f%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">keyword?</span></span></a></td></tr><tr><td><a href="keywords.html#%28def._%28%28quote._~23~25kernel%29._keyword-~3estring%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">keyword-<wbr></wbr>>string</span></span></a></td></tr><tr><td><a href="keywords.html#%28def._%28%28quote._~23~25kernel%29._string-~3ekeyword%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">string-<wbr></wbr>>keyword</span></span></a></td></tr><tr><td><a href="keywords.html#%28def._%28%28quote._~23~25kernel%29._keyword~3c~3f%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">keyword<?</span></span></a></td></tr><tr><td><span class="tocsublinknumber">4.9.1<tt> </tt></span><a href="keywords.html#%28part._.Additional_.Keyword_.Functions%29" class="tocsubseclink" data-pltdoc="x">Additional Keyword Functions</a></td></tr><tr><td><a href="keywords.html#%28def._%28%28lib._racket%2Fkeyword..rkt%29._keyword-~3eimmutable-string%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">keyword-<wbr></wbr>>immutable-<wbr></wbr>string</span></span></a></td></tr></table></div></div><div class="maincolumn"><div class="main"><div class="navsettop"><span class="navleft"><form class="searchform"><input class="searchbox" id="searchbox" type="text" tabindex="1" placeholder="...search manuals..." title="Enter a search string to search the manuals" onkeypress="return DoSearchKey(event, this, "8.6", "../");"/></form> <a href="https://docs.racket-lang.org/index.html" title="up to the documentation top" data-pltdoc="x" onclick="return GotoPLTRoot("8.6");">top</a><span class="tocsettoggle"> <a href="javascript:void(0);" title="show/hide table of contents" onclick="TocsetToggle();">contents</a></span></span><span class="navright"> <a href="regexp.html" title="backward to "4.8 Regular Expressions"" data-pltdoc="x">← prev</a> <a href="data.html" title="up to "4 Datatypes"" data-pltdoc="x">up</a> <a href="pairs.html" title="forward to "4.10 Pairs and Lists"" data-pltdoc="x">next →</a></span> </div><h4 x-source-module="(lib "scribblings/reference/reference.scrbl")" x-source-pkg="racket-doc" x-part-tag=""keywords"">4.9<tt> </tt><a name="(part._keywords)"></a>Keywords</h4><blockquote class="refpara"><blockquote class="refcolumn"><blockquote class="refcontent"><p><span class="imageleft"><img src="finger.png" alt="+" width="24" height="24"/></span><a href="https://download.racket-lang.org/releases/8.6/doc/local-redirect/index.html?doc=guide&rel=keywords.html&version=8.6" class="Sq" data-pltdoc="x">Keywords</a> in <a href="https://download.racket-lang.org/releases/8.6/doc/local-redirect/index.html?doc=guide&rel=index.html&version=8.6" class="Sq" data-pltdoc="x">The Racket Guide</a> introduces keywords.</p></blockquote></blockquote></blockquote><p>A <a name="(tech._keyword)"></a><span style="font-style: italic">keyword</span> is like an <a href="reader.html#%28tech._interned%29" class="techoutside" data-pltdoc="x"><span class="techinside">interned</span></a> symbol, but its printed
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form starts with <span class="RktInBG"><span class="hspace"></span><span class="RktIn">#:</span><span class="hspace"></span></span>, and a keyword cannot be used as an
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identifier. Furthermore, a keyword by itself is not a valid
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expression, though a keyword can be <span class="RktSym"><a href="quote.html#%28form._%28%28quote._~23~25kernel%29._quote%29%29" class="RktStxLink" data-pltdoc="x">quote</a></span>d to form an
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expression that produces the symbol.</p><p>Two keywords are <span class="RktSym"><a href="Equality.html#%28def._%28%28quote._~23~25kernel%29._eq~3f%29%29" class="RktValLink" data-pltdoc="x">eq?</a></span> if and only if they print the same
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(i.e., keywords are always <a href="reader.html#%28tech._interned%29" class="techoutside" data-pltdoc="x"><span class="techinside">interned</span></a>).</p><p>Like symbols, keywords are only weakly held by the internal keyword
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table; see <a href="symbols.html" data-pltdoc="x">Symbols</a> for more information.</p><p>See <a href="reader.html#%28part._parse-keyword%29" data-pltdoc="x">Reading Keywords</a>
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for information on <span class="RktSym"><a href="Reading.html#%28def._%28%28quote._~23~25kernel%29._read%29%29" class="RktValLink" data-pltdoc="x">read</a></span>ing
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keywords and <a href="printing.html#%28part._print-keyword%29" data-pltdoc="x">Printing Keywords</a>
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for information on <span class="RktSym"><a href="Writing.html#%28def._%28%28quote._~23~25kernel%29._print%29%29" class="RktValLink" data-pltdoc="x">print</a></span>ing keywords.</p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._keyword~3f))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="keywords.html#%28def._%28%28quote._~23~25kernel%29._keyword~3f%29%29" class="RktValDef RktValLink" data-pltdoc="x">keyword?</a></span></span><span class="hspace"> </span><span class="RktVar">v</span><span class="RktPn">)</span><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktSym"><a href="booleans.html#%28def._%28%28quote._~23~25kernel%29._boolean~3f%29%29" class="RktValLink" data-pltdoc="x">boolean?</a></span></p></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">v</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._any%2Fc%29%29" class="RktValLink" data-pltdoc="x">any/c</a></span></td></tr></table></blockquote></div><div class="SIntrapara">Returns <span class="RktVal">#t</span> if <span class="RktVar">v</span> is a keyword, <span class="RktVal">#f</span> otherwise.</div></p><p><div class="SIntrapara">Examples:</div><div class="SIntrapara"><blockquote class="SCodeFlow"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym"><a href="keywords.html#%28def._%28%28quote._~23~25kernel%29._keyword~3f%29%29" class="RktValLink" data-pltdoc="x">keyword?</a></span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">#:apple</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">#t</span></p></td></tr><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym"><a href="keywords.html#%28def._%28%28quote._~23~25kernel%29._keyword~3f%29%29" class="RktValLink" data-pltdoc="x">keyword?</a></span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">define</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">#f</span></p></td></tr><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym"><a href="keywords.html#%28def._%28%28quote._~23~25kernel%29._keyword~3f%29%29" class="RktValLink" data-pltdoc="x">keyword?</a></span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">#:define</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">#t</span></p></td></tr></table></blockquote></div></p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._keyword-~3estring))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="keywords.html#%28def._%28%28quote._~23~25kernel%29._keyword-~3estring%29%29" class="RktValDef RktValLink" data-pltdoc="x">keyword->string</a></span></span><span class="hspace"> </span><span class="RktVar">keyword</span><span class="RktPn">)</span><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktSym"><a href="strings.html#%28def._%28%28quote._~23~25kernel%29._string~3f%29%29" class="RktValLink" data-pltdoc="x">string?</a></span></p></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">keyword</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="keywords.html#%28def._%28%28quote._~23~25kernel%29._keyword~3f%29%29" class="RktValLink" data-pltdoc="x">keyword?</a></span></td></tr></table></blockquote></div><div class="SIntrapara">Returns a string for the <span class="RktSym"><a href="Writing.html#%28def._%28%28quote._~23~25kernel%29._display%29%29" class="RktValLink" data-pltdoc="x">display</a></span>ed form of <span class="RktVar">keyword</span>,
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not including the leading <span class="RktInBG"><span class="hspace"></span><span class="RktIn">#:</span><span class="hspace"></span></span>.</div></p><p>See also <span class="RktSym"><a href="keywords.html#%28def._%28%28lib._racket%2Fkeyword..rkt%29._keyword-~3eimmutable-string%29%29" class="RktValLink" data-pltdoc="x">keyword->immutable-string</a></span> from
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<a href="keywords.html#%28mod-path._racket%2Fkeyword%29" class="RktModLink" data-pltdoc="x"><span class="RktSym">racket/keyword</span></a>.</p><p><div class="SIntrapara">Example:</div><div class="SIntrapara"><blockquote class="SCodeFlow"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym"><a href="keywords.html#%28def._%28%28quote._~23~25kernel%29._keyword-~3estring%29%29" class="RktValLink" data-pltdoc="x">keyword->string</a></span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">#:apple</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">"apple"</span></p></td></tr></table></blockquote></div></p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._string-~3ekeyword))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="keywords.html#%28def._%28%28quote._~23~25kernel%29._string-~3ekeyword%29%29" class="RktValDef RktValLink" data-pltdoc="x">string->keyword</a></span></span><span class="hspace"> </span><span class="RktVar">str</span><span class="RktPn">)</span><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktSym"><a href="keywords.html#%28def._%28%28quote._~23~25kernel%29._keyword~3f%29%29" class="RktValLink" data-pltdoc="x">keyword?</a></span></p></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">str</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="strings.html#%28def._%28%28quote._~23~25kernel%29._string~3f%29%29" class="RktValLink" data-pltdoc="x">string?</a></span></td></tr></table></blockquote></div><div class="SIntrapara">Returns a keyword whose <span class="RktSym"><a href="Writing.html#%28def._%28%28quote._~23~25kernel%29._display%29%29" class="RktValLink" data-pltdoc="x">display</a></span>ed form is the same as that of
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<span class="RktVar">str</span>, but with a leading <span class="RktInBG"><span class="hspace"></span><span class="RktIn">#:</span><span class="hspace"></span></span>.</div></p><p><div class="SIntrapara">Example:</div><div class="SIntrapara"><blockquote class="SCodeFlow"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym"><a href="keywords.html#%28def._%28%28quote._~23~25kernel%29._string-~3ekeyword%29%29" class="RktValLink" data-pltdoc="x">string->keyword</a></span><span class="hspace"> </span><span class="RktVal">"apple"</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">'#:apple</span></p></td></tr></table></blockquote></div></p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._keyword~3c~3f))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="keywords.html#%28def._%28%28quote._~23~25kernel%29._keyword~3c~3f%29%29" class="RktValDef RktValLink" data-pltdoc="x">keyword<?</a></span></span><span class="hspace"> </span><span class="RktVar">a-keyword</span><span class="hspace"> </span><span class="RktVar">b-keyword</span><span class="hspace"> </span><span class="RktMeta">...</span><span class="RktPn">)</span><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktSym"><a href="booleans.html#%28def._%28%28quote._~23~25kernel%29._boolean~3f%29%29" class="RktValLink" data-pltdoc="x">boolean?</a></span></p></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">a-keyword</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="keywords.html#%28def._%28%28quote._~23~25kernel%29._keyword~3f%29%29" class="RktValLink" data-pltdoc="x">keyword?</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">b-keyword</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="keywords.html#%28def._%28%28quote._~23~25kernel%29._keyword~3f%29%29" class="RktValLink" data-pltdoc="x">keyword?</a></span></td></tr></table></blockquote></div><div class="SIntrapara">Returns <span class="RktVal">#t</span> if the arguments are sorted, where the comparison
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for each pair of keywords is the same as using
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<span class="RktSym"><a href="keywords.html#%28def._%28%28quote._~23~25kernel%29._keyword-~3estring%29%29" class="RktValLink" data-pltdoc="x">keyword->string</a></span> with <span class="RktSym"><a href="bytestrings.html#%28def._%28%28quote._~23~25kernel%29._string-~3ebytes%2Futf-8%29%29" class="RktValLink" data-pltdoc="x">string->bytes/utf-8</a></span> and
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<span class="RktSym"><a href="bytestrings.html#%28def._%28%28quote._~23~25kernel%29._bytes~3c~3f%29%29" class="RktValLink" data-pltdoc="x">bytes<?</a></span>.</div></p><p><div class="SIntrapara">Example:</div><div class="SIntrapara"><blockquote class="SCodeFlow"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym"><a href="keywords.html#%28def._%28%28quote._~23~25kernel%29._keyword~3c~3f%29%29" class="RktValLink" data-pltdoc="x">keyword<?</a></span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">#:apple</span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">#:banana</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">#t</span></p></td></tr></table></blockquote></div></p><p class="SHistory">Changed in version 7.0.0.13 of package <span class="stt">base</span>: Allow one argument, in addition to allowing two or more.</p><h5 x-source-module="(lib "scribblings/reference/reference.scrbl")" x-source-pkg="racket-doc" x-part-tag=""Additional_Keyword_Functions"">4.9.1<tt> </tt><a name="(part._.Additional_.Keyword_.Functions)"></a><a name="(mod-path._racket/keyword)"></a>Additional Keyword Functions</h5><p><div class="SIntrapara"><table cellspacing="0" cellpadding="0" class="defmodule"><tr><td align="left"><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="require.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._require%29%29" class="RktStxLink" data-pltdoc="x">require</a></span><span class="stt"> </span><a href="keywords.html#%28mod-path._racket%2Fkeyword%29" class="RktModLink" data-pltdoc="x"><span class="RktSym">racket/keyword</span></a><span class="RktPn">)</span></td><td align="right"><span class="RpackageSpec"><span class="Smaller"> package:</span> <a href="https://pkgs.racket-lang.org/package/base" title="Install this package using `raco pkg install base`"><span class="stt">base</span></a></span></td></tr></table></div><div class="SIntrapara">The bindings documented in this section are provided by the <a href="keywords.html#%28mod-path._racket%2Fkeyword%29" class="RktModLink" data-pltdoc="x"><span class="RktSym">racket/keyword</span></a> and <a href="index.html" class="RktModLink" data-pltdoc="x"><span class="RktSym">racket</span></a> libraries, but not <a href="index.html" class="RktModLink" data-pltdoc="x"><span class="RktSym">racket/base</span></a>.</div></p><p class="SHistory">Added in version 7.6 of package <span class="stt">base</span>.</p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((lib._racket/keyword..rkt)._keyword-~3eimmutable-string))"></a><span title="Provided from: racket/keyword, racket | Package: base"><span class="RktSym"><a href="keywords.html#%28def._%28%28lib._racket%2Fkeyword..rkt%29._keyword-~3eimmutable-string%29%29" class="RktValDef RktValLink" data-pltdoc="x">keyword->immutable-string</a></span></span><span class="hspace"> </span><span class="RktVar">sym</span><span class="RktPn">)</span><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._and%2Fc%29%29" class="RktValLink" data-pltdoc="x">and/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="strings.html#%28def._%28%28quote._~23~25kernel%29._string~3f%29%29" class="RktValLink" data-pltdoc="x">string?</a></span><span class="hspace"> </span><span class="RktSym"><a href="booleans.html#%28def._%28%28quote._~23~25kernel%29._immutable~3f%29%29" class="RktValLink" data-pltdoc="x">immutable?</a></span><span class="RktPn">)</span></p></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">sym</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="keywords.html#%28def._%28%28quote._~23~25kernel%29._keyword~3f%29%29" class="RktValLink" data-pltdoc="x">keyword?</a></span></td></tr></table></blockquote></div><div class="SIntrapara">Like <span class="RktSym"><a href="keywords.html#%28def._%28%28quote._~23~25kernel%29._keyword-~3estring%29%29" class="RktValLink" data-pltdoc="x">keyword->string</a></span>, but the result is an immutable string,
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not necessarily freshly allocated.</div></p><p><div class="SIntrapara">Examples:</div><div class="SIntrapara"><blockquote class="SCodeFlow"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym"><a href="keywords.html#%28def._%28%28lib._racket%2Fkeyword..rkt%29._keyword-~3eimmutable-string%29%29" class="RktValLink" data-pltdoc="x">keyword->immutable-string</a></span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">#:apple</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">"apple"</span></p></td></tr><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym"><a href="booleans.html#%28def._%28%28quote._~23~25kernel%29._immutable~3f%29%29" class="RktValLink" data-pltdoc="x">immutable?</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="keywords.html#%28def._%28%28lib._racket%2Fkeyword..rkt%29._keyword-~3eimmutable-string%29%29" class="RktValLink" data-pltdoc="x">keyword->immutable-string</a></span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">#:apple</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">#t</span></p></td></tr></table></blockquote></div></p><p class="SHistory">Added in version 7.6 of package <span class="stt">base</span>.</p><div class="navsetbottom"><span class="navleft"><form class="searchform"><input class="searchbox" id="searchbox" type="text" tabindex="1" placeholder="...search manuals..." title="Enter a search string to search the manuals" onkeypress="return DoSearchKey(event, this, "8.6", "../");"/></form> <a href="https://docs.racket-lang.org/index.html" title="up to the documentation top" data-pltdoc="x" onclick="return GotoPLTRoot("8.6");">top</a><span class="tocsettoggle"> <a href="javascript:void(0);" title="show/hide table of contents" onclick="TocsetToggle();">contents</a></span></span><span class="navright"> <a href="regexp.html" title="backward to "4.8 Regular Expressions"" data-pltdoc="x">← prev</a> <a href="data.html" title="up to "4 Datatypes"" data-pltdoc="x">up</a> <a href="pairs.html" title="forward to "4.10 Pairs and Lists"" data-pltdoc="x">next →</a></span> </div></div></div><div id="contextindicator"> </div></body></html> |