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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>14.3 The racket/load Language</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="../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="tocviewlink" 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="tocviewselflink" 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>14 </td><td><a href="security.html" class="tocviewlink" data-pltdoc="x">Reflection and Security</a></td></tr></table><div class="tocviewsublistbottom" style="display: block;" id="tocview_1"><table cellspacing="0" cellpadding="0"><tr><td align="right">14.1 </td><td><a href="Namespaces.html" class="tocviewlink" data-pltdoc="x">Namespaces</a></td></tr><tr><td align="right">14.2 </td><td><a href="eval.html" class="tocviewlink" data-pltdoc="x">Evaluation and Compilation</a></td></tr><tr><td align="right">14.3 </td><td><a href="load-lang.html" class="tocviewselflink" data-pltdoc="x">The <span class="RktModLink"><span class="RktSym">racket/<span class="mywbr"> </span>load</span></span> Language</a></td></tr><tr><td align="right">14.4 </td><td><a href="Module_Names_and_Loading.html" class="tocviewlink" data-pltdoc="x">Module Names and Loading</a></td></tr><tr><td align="right">14.5 </td><td><a href="chaperones.html" class="tocviewlink" data-pltdoc="x">Impersonators and Chaperones</a></td></tr><tr><td align="right">14.6 </td><td><a href="securityguards.html" class="tocviewlink" data-pltdoc="x">Security Guards</a></td></tr><tr><td align="right">14.7 </td><td><a href="custodians.html" class="tocviewlink" data-pltdoc="x">Custodians</a></td></tr><tr><td align="right">14.8 </td><td><a href="threadgroups.html" class="tocviewlink" data-pltdoc="x">Thread Groups</a></td></tr><tr><td align="right">14.9 </td><td><a href="inspectors.html" class="tocviewlink" data-pltdoc="x">Structure Inspectors</a></td></tr><tr><td align="right">14.10 </td><td><a href="modprotect.html" class="tocviewlink" data-pltdoc="x">Code Inspectors</a></td></tr><tr><td align="right">14.11 </td><td><a href="plumbers.html" class="tocviewlink" data-pltdoc="x">Plumbers</a></td></tr><tr><td align="right">14.12 </td><td><a href="Sandboxed_Evaluation.html" class="tocviewlink" data-pltdoc="x">Sandboxed Evaluation</a></td></tr><tr><td align="right">14.13 </td><td><a href="repl-module.html" class="tocviewlink" data-pltdoc="x">The <span class="RktModLink"><span class="RktSym">racket/<span class="mywbr"> </span>repl</span></span> Library</a></td></tr><tr><td align="right">14.14 </td><td><a href="linklets.html" class="tocviewlink" data-pltdoc="x">Linklets and the Core Compiler</a></td></tr></table></div></div></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="eval.html" title="backward to "14.2 Evaluation and Compilation"" data-pltdoc="x">← prev</a> <a href="security.html" title="up to "14 Reflection and Security"" data-pltdoc="x">up</a> <a href="Module_Names_and_Loading.html" title="forward to "14.4 Module Names and Loading"" data-pltdoc="x">next →</a></span> </div><h4 x-source-module="(lib "scribblings/reference/reference.scrbl")" x-source-pkg="racket-doc" x-part-tag=""load-lang"">14.3<tt> </tt><a name="(part._load-lang)"></a><a name="(mod-path._racket/load)"></a>The <a href="load-lang.html" class="RktModLink" data-pltdoc="x"><span class="RktSym">racket/load</span></a> Language</h4><p><table cellspacing="0" cellpadding="0" class="defmodule"><tr><td align="left"><span class="hspace"> </span><a href="https://download.racket-lang.org/releases/8.6/doc/local-redirect/index.html?doc=guide&rel=Module_Syntax.html%23%2528part._hash-lang%2529&version=8.6" class="RktModLink Sq" data-pltdoc="x"><span class="RktMod">#lang</span></a><span class="hspace"> </span><a href="load-lang.html" class="RktModLink" data-pltdoc="x"><span class="RktSym">racket/load</span></a></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></p><p>The <a href="load-lang.html" class="RktModLink" data-pltdoc="x"><span class="RktSym">racket/load</span></a> language supports evaluation where
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each top-level form in the module body is separately passed to
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<span class="RktSym"><a href="eval.html#%28def._%28%28quote._~23~25kernel%29._eval%29%29" class="RktValLink" data-pltdoc="x">eval</a></span> in the same way as for <span class="RktSym"><a href="eval.html#%28def._%28%28quote._~23~25kernel%29._load%29%29" class="RktValLink" data-pltdoc="x">load</a></span>.</p><p>The namespace for evaluation shares the <a href="syntax-model.html#%28tech._module._registry%29" class="techoutside" data-pltdoc="x"><span class="techinside">module registry</span></a> with
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the <a href="load-lang.html" class="RktModLink" data-pltdoc="x"><span class="RktSym">racket/load</span></a> module instance, but it has a separate
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top-level environment, and it is initialized with the bindings of
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<a href="index.html" class="RktModLink" data-pltdoc="x"><span class="RktSym">racket</span></a>. A single namespace is created for each
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instance of the <a href="load-lang.html" class="RktModLink" data-pltdoc="x"><span class="RktSym">racket/load</span></a> module (i.e., multiple
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modules using the <a href="load-lang.html" class="RktModLink" data-pltdoc="x"><span class="RktSym">racket/load</span></a> language share a
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namespace). The <span class="RktSym">racket/load</span> library exports only
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<span class="RktSym">#%module-begin</span> and <span class="RktSym">#%top-interaction</span>
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forms that effectively swap in the evaluation namespace and call
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<span class="RktSym"><a href="eval.html#%28def._%28%28quote._~23~25kernel%29._eval%29%29" class="RktValLink" data-pltdoc="x">eval</a></span>.</p><p>For example, the body of a module using <span class="RktSym">racket/load</span> can
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include <span class="RktSym"><a href="module.html#%28form._%28%28quote._~23~25kernel%29._module%29%29" class="RktStxLink" data-pltdoc="x">module</a></span> forms, so that running the following module
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prints <span class="RktRes">5</span>:</p><blockquote class="SCodeFlow"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><a href="https://download.racket-lang.org/releases/8.6/doc/local-redirect/index.html?doc=guide&rel=Module_Syntax.html%23%2528part._hash-lang%2529&version=8.6" class="RktModLink Sq" data-pltdoc="x"><span class="RktMod">#lang</span></a><span class="hspace"> </span><a href="load-lang.html" class="RktModLink" data-pltdoc="x"><span class="RktSym">racket/load</span></a></td></tr><tr><td><span class="hspace"> </span></td></tr><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="module.html#%28form._%28%28quote._~23~25kernel%29._module%29%29" class="RktStxLink" data-pltdoc="x">module</a></span><span class="hspace"> </span><span class="RktSym">m</span><span class="hspace"> </span><span class="RktSym">racket/base</span></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="require.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._provide%29%29" class="RktStxLink" data-pltdoc="x">provide</a></span><span class="hspace"> </span><span class="RktSym">x</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="define.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._define%29%29" class="RktStxLink" data-pltdoc="x">define</a></span><span class="hspace"> </span><span class="RktSym">x</span><span class="hspace"> </span><span class="RktVal">5</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span></td></tr><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="module.html#%28form._%28%28quote._~23~25kernel%29._module%29%29" class="RktStxLink" data-pltdoc="x">module</a></span><span class="hspace"> </span><span class="RktSym">n</span><span class="hspace"> </span><span class="RktSym">racket/base</span></td></tr><tr><td><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="hspace"> </span><span class="RktVal">'</span><span class="RktVal">m</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="Writing.html#%28def._%28%28quote._~23~25kernel%29._display%29%29" class="RktValLink" data-pltdoc="x">display</a></span><span class="hspace"> </span><span class="RktSym">x</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span></td></tr><tr><td><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="hspace"> </span><span class="RktVal">'</span><span class="RktVal">n</span><span class="RktPn">)</span></td></tr></table></blockquote><p>Definitions in a module using <span class="RktSym">racket/load</span> are evaluated in
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the current namespace, which means that <span class="RktSym"><a href="eval.html#%28def._%28%28quote._~23~25kernel%29._load%29%29" class="RktValLink" data-pltdoc="x">load</a></span> and
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<span class="RktSym"><a href="eval.html#%28def._%28%28quote._~23~25kernel%29._eval%29%29" class="RktValLink" data-pltdoc="x">eval</a></span> can see the definitions. For example, running the
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following module prints <span class="RktRes">6</span>:</p><blockquote class="SCodeFlow"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><a href="https://download.racket-lang.org/releases/8.6/doc/local-redirect/index.html?doc=guide&rel=Module_Syntax.html%23%2528part._hash-lang%2529&version=8.6" class="RktModLink Sq" data-pltdoc="x"><span class="RktMod">#lang</span></a><span class="hspace"> </span><a href="load-lang.html" class="RktModLink" data-pltdoc="x"><span class="RktSym">racket/load</span></a></td></tr><tr><td><span class="hspace"> </span></td></tr><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="define.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._define%29%29" class="RktStxLink" data-pltdoc="x">define</a></span><span class="hspace"> </span><span class="RktSym">x</span><span class="hspace"> </span><span class="RktVal">6</span><span class="RktPn">)</span></td></tr><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="Writing.html#%28def._%28%28quote._~23~25kernel%29._display%29%29" class="RktValLink" data-pltdoc="x">display</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="eval.html#%28def._%28%28quote._~23~25kernel%29._eval%29%29" class="RktValLink" data-pltdoc="x">eval</a></span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">x</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr></table></blockquote><p>Since all forms within a <a href="load-lang.html" class="RktModLink" data-pltdoc="x"><span class="RktSym">racket/load</span></a> module are
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evaluated in the top level, bindings cannot be exported from the
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module using <span class="RktSym"><a href="require.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._provide%29%29" class="RktStxLink" data-pltdoc="x">provide</a></span>. Similarly, since evaluation of the
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module-body forms is inherently dynamic, compilation of the module
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provides essentially no benefit. For these reasons, use
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<a href="load-lang.html" class="RktModLink" data-pltdoc="x"><span class="RktSym">racket/load</span></a> for interactive exploration of top-level
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forms only, and not for constructing larger programs.</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="eval.html" title="backward to "14.2 Evaluation and Compilation"" data-pltdoc="x">← prev</a> <a href="security.html" title="up to "14 Reflection and Security"" data-pltdoc="x">up</a> <a href="Module_Names_and_Loading.html" title="forward to "14.4 Module Names and Loading"" data-pltdoc="x">next →</a></span> </div></div></div><div id="contextindicator"> </div></body></html> |