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<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"/><title>11.4&nbsp;Pagetree</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="manual-style.css" title="default"/><link rel="stylesheet" type="text/css" href="manual-racket.css" title="default"/><link rel="stylesheet" type="text/css" href="mb.css" title="default"/><script type="text/javascript" src="scribble-common.js"></script><script type="text/javascript" src="manual-racket.js"></script><!--[if IE 6]><style type="text/css">.SIEHidden { overflow: hidden; }</style><![endif]--></head><body id="scribble-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,&quot;tocview_0&quot;);">&#9658;</a></td><td></td><td><a href="index.html" class="tocviewlink" data-pltdoc="x">Pollen:<span class="mywbr"> &nbsp;</span> the book is a program</a></td></tr></table></div><div class="tocviewsublisttop" style="display: none;" id="tocview_0"><table cellspacing="0" cellpadding="0"><tr><td align="right">1&nbsp;</td><td><a href="Installation.html" class="tocviewlink" data-pltdoc="x">Installation</a></td></tr><tr><td align="right">2&nbsp;</td><td><a href="quick-tour.html" class="tocviewlink" data-pltdoc="x">Quick tour</a></td></tr><tr><td align="right">3&nbsp;</td><td><a href="Backstory.html" class="tocviewlink" data-pltdoc="x">Backstory</a></td></tr><tr><td align="right">4&nbsp;</td><td><a href="big-picture.html" class="tocviewlink" data-pltdoc="x">The big picture</a></td></tr><tr><td align="right">5&nbsp;</td><td><a href="first-tutorial.html" class="tocviewlink" data-pltdoc="x">First tutorial</a></td></tr><tr><td align="right">6&nbsp;</td><td><a href="second-tutorial.html" class="tocviewlink" data-pltdoc="x">Second tutorial</a></td></tr><tr><td align="right">7&nbsp;</td><td><a href="third-tutorial.html" class="tocviewlink" data-pltdoc="x">Third tutorial</a></td></tr><tr><td align="right">8&nbsp;</td><td><a href="raco-pollen.html" class="tocviewlink" data-pltdoc="x">Using <span class="stt">raco pollen</span></a></td></tr><tr><td align="right">9&nbsp;</td><td><a href="File_formats.html" class="tocviewlink" data-pltdoc="x">File formats</a></td></tr><tr><td align="right">10&nbsp;</td><td><a href="reader.html" class="tocviewlink" data-pltdoc="x">&#9674; command overview</a></td></tr><tr><td align="right">11&nbsp;</td><td><a href="Module_reference.html" class="tocviewselflink" data-pltdoc="x">Module reference</a></td></tr><tr><td align="right">12&nbsp;</td><td><a href="Acknowledgments.html" class="tocviewlink" data-pltdoc="x">Acknowledgments</a></td></tr><tr><td align="right">13&nbsp;</td><td><a href="License___source_code.html" class="tocviewlink" data-pltdoc="x">License &amp; source code</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,&quot;tocview_1&quot;);">&#9660;</a></td><td>11&nbsp;</td><td><a href="Module_reference.html" class="tocviewlink" data-pltdoc="x">Module reference</a></td></tr></table><div class="tocviewsublist" style="display: block;" id="tocview_1"><table cellspacing="0" cellpadding="0"><tr><td align="right">11.1&nbsp;</td><td><a href="Cache.html" class="tocviewlink" data-pltdoc="x">Cache</a></td></tr><tr><td align="right">11.2&nbsp;</td><td><a href="Decode.html" class="tocviewlink" data-pltdoc="x">Decode</a></td></tr><tr><td align="right">11.3&nbsp;</td><td><a href="file-types.html" class="tocviewlink" data-pltdoc="x">File</a></td></tr><tr><td align="right">11.4&nbsp;</td><td><a href="Pagetree.html" class="tocviewselflink" data-pltdoc="x">Pagetree</a></td></tr><tr><td align="right">11.5&nbsp;</td><td><a href="Render.html" class="tocviewlink" data-pltdoc="x">Render</a></td></tr><tr><td align="right">11.6&nbsp;</td><td><a href="Template.html" class="tocviewlink" data-pltdoc="x">Template</a></td></tr><tr><td align="right">11.7&nbsp;</td><td><a href="Tag.html" class="tocviewlink" data-pltdoc="x">Tag</a></td></tr><tr><td align="right">11.8&nbsp;</td><td><a href="Top.html" class="tocviewlink" data-pltdoc="x">Top</a></td></tr><tr><td align="right">11.9&nbsp;</td><td><a href="World.html" class="tocviewlink" data-pltdoc="x">World</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>11.4&nbsp;</td><td><a href="Pagetree.html" class="tocviewselflink" data-pltdoc="x">Pagetree</a></td></tr></table><div class="tocviewsublistbottom" style="display: none;" id="tocview_2"><table cellspacing="0" cellpadding="0"><tr><td align="right">11.4.1&nbsp;</td><td><a href="Pagetree.html#%28part._.Making_pagetrees_with_a_source_file%29" class="tocviewlink" data-pltdoc="x">Making pagetrees with a source file</a></td></tr><tr><td align="right">11.4.2&nbsp;</td><td><a href="Pagetree.html#%28part._.Making_pagetrees_by_hand%29" class="tocviewlink" data-pltdoc="x">Making pagetrees by hand</a></td></tr><tr><td align="right">11.4.3&nbsp;</td><td><a href="Pagetree.html#%28part._.Using_pagetrees_for_navigation%29" class="tocviewlink" data-pltdoc="x">Using pagetrees for navigation</a></td></tr><tr><td align="right">11.4.4&nbsp;</td><td><a href="Pagetree.html#%28part._.Using_index_ptree_in_the_dashboard%29" class="tocviewlink" data-pltdoc="x">Using <span class="stt">index.ptree</span> in the dashboard</a></td></tr><tr><td align="right">11.4.5&nbsp;</td><td><a href="Pagetree.html#%28part._.Using_pagetrees_with_raco_pollen_render%29" class="tocviewlink" data-pltdoc="x">Using pagetrees with <span class="stt">raco pollen render</span></a></td></tr><tr><td align="right">11.4.6&nbsp;</td><td><a href="Pagetree.html#%28part._.Functions%29" class="tocviewlink" data-pltdoc="x">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><span class="tocsublinknumber">11.4.1<tt>&nbsp;</tt></span><a href="#%28part._.Making_pagetrees_with_a_source_file%29" class="tocsubseclink" data-pltdoc="x">Making pagetrees with a source file</a></td></tr><tr><td><span class="tocsublinknumber">11.4.2<tt>&nbsp;</tt></span><a href="#%28part._.Making_pagetrees_by_hand%29" class="tocsubseclink" data-pltdoc="x">Making pagetrees by hand</a></td></tr><tr><td><span class="tocsublinknumber">11.4.3<tt>&nbsp;</tt></span><a href="#%28part._.Using_pagetrees_for_navigation%29" class="tocsubseclink" data-pltdoc="x">Using pagetrees for navigation</a></td></tr><tr><td><span class="tocsublinknumber">11.4.4<tt>&nbsp;</tt></span><a href="#%28part._.Using_index_ptree_in_the_dashboard%29" class="tocsubseclink" data-pltdoc="x">Using <span class="stt">index.ptree</span> in the dashboard</a></td></tr><tr><td><span class="tocsublinknumber">11.4.5<tt>&nbsp;</tt></span><a href="#%28part._.Using_pagetrees_with_raco_pollen_render%29" class="tocsubseclink" data-pltdoc="x">Using pagetrees with <span class="stt">raco pollen render</span></a></td></tr><tr><td><span class="tocsublinknumber">11.4.6<tt>&nbsp;</tt></span><a href="#%28part._.Functions%29" class="tocsubseclink" data-pltdoc="x">Functions</a></td></tr><tr><td><span class="tocsublinknumber">11.4.6.1<tt>&nbsp;</tt></span><a href="#%28part._.Predicates___validation%29" class="tocsubseclink" data-pltdoc="x">Predicates &amp; validation</a></td></tr><tr><td><a href="#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagetree~3f%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">pagetree?</span></span></a></td></tr><tr><td><a href="#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._validate-pagetree%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">validate-<wbr></wbr>pagetree</span></span></a></td></tr><tr><td><a href="#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagenode~3f%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">pagenode?</span></span></a></td></tr><tr><td><a href="#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagenodeish~3f%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">pagenodeish?</span></span></a></td></tr><tr><td><a href="#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._-~3epagenode%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink"><span class="nobreak">-<wbr></wbr>&gt;</span>pagenode</span></span></a></td></tr><tr><td><span class="tocsublinknumber">11.4.6.2<tt>&nbsp;</tt></span><a href="#%28part._.Navigation%29" class="tocsubseclink" data-pltdoc="x">Navigation</a></td></tr><tr><td><a href="#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._current-pagetree%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">current-<wbr></wbr>pagetree</span></span></a></td></tr><tr><td><a href="#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._parent%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">parent</span></span></a></td></tr><tr><td><a href="#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._children%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">children</span></span></a></td></tr><tr><td><a href="#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._siblings%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">siblings</span></span></a></td></tr><tr><td><a href="#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._previous%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">previous</span></span></a></td></tr><tr><td><a href="#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._previous%2A%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">previous*</span></span></a></td></tr><tr><td><a href="#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._next%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">next</span></span></a></td></tr><tr><td><a href="#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._next%2A%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">next*</span></span></a></td></tr><tr><td><span class="tocsublinknumber">11.4.6.3<tt>&nbsp;</tt></span><a href="#%28part._.Utilities%29" class="tocsubseclink" data-pltdoc="x">Utilities</a></td></tr><tr><td><a href="#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagetree-~3elist%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">pagetree-<wbr></wbr>&gt;list</span></span></a></td></tr><tr><td><a href="#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._in-pagetree~3f%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">in-<wbr></wbr>pagetree?</span></span></a></td></tr><tr><td><a href="#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._path-~3epagenode%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">path-<wbr></wbr>&gt;pagenode</span></span></a></td></tr></table></div></div><div class="maincolumn"><div class="main"><div class="versionbox"><span class="version">6.1.0.8</span></div><div class="navsettop"><span class="navleft"><div class="nosearchform"></div>&nbsp;&nbsp;</span><span class="navright">&nbsp;&nbsp;<a href="file-types.html" title="backward to &quot;11.3 File&quot;" data-pltdoc="x">&larr; prev</a>&nbsp;&nbsp;<a href="Module_reference.html" title="up to &quot;11 Module reference&quot;" data-pltdoc="x">up</a>&nbsp;&nbsp;<a href="Render.html" title="forward to &quot;11.5 Render&quot;" data-pltdoc="x">next &rarr;</a></span>&nbsp;</div><h4>11.4<tt>&nbsp;</tt><a name="(part._.Pagetree)"></a><a name="(mod-path._pollen/pagetree)"></a>Pagetree</h4><p><table cellspacing="0" cellpadding="0" class="defmodule"><tr><td align="left"><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/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="Pagetree.html" class="RktModLink" data-pltdoc="x"><span class="RktSym">pollen/pagetree</span></a><span class="RktPn">)</span></td><td align="right"><span class="RpackageSpec"><span class="Smaller">&nbsp;package:</span> <span class="stt">pollen</span></span></td></tr></table></p><p>Books and other long documents are usually organized in a structured way &#8212;&#160;at minimum they have a sequence of pages, but more often they have sections with subsequences within. Individual pages in a Pollen project don&rsquo;t know anything about how they&rsquo;re connected to other pages. In theory, you could maintain this information within the source files. But this would be a poor use of human energy.</p><p>Instead, use a pagetree. A <span style="font-style: italic">pagetree</span> is a simple abstraction for defining &amp; working with sequences of <span style="font-style: italic">pagenodes</span>. Typically these pagenodes will be the names of output files in your project.</p><p>&ldquo;So it&rsquo;s a list of web-page filenames?&rdquo; Sort of. When I think of a web page, I think of an actual file on a disk. Keeping with Pollen&rsquo;s orientation toward dynamic rendering, pagenodes may &#8212;&#160;and often do &#8212;&#160;refer to files that don&rsquo;t yet exist. Moreover, by referring to output names rather than source names, you retain the flexibility to change the kind of source associated with a particular pagenode (e.g., from preprocessor source to Pollen markup).</p><p>Pagetrees can be flat or hierarchical. A flat pagetree is just a <a href="http://docs.racket-lang.org/guide/Lists__Iteration__and_Recursion.html" data-pltdoc="x">list</a> of pagenodes. A hierarchical pagetree can also contain recursively nested lists of pagenodes. But you needn&rsquo;t pay attention to this distinction, as the pagetree functions don&rsquo;t care which kind you use. Neither do I.</p><p>Pagetrees surface throughout the Pollen system. They&rsquo;re primarily used for navigation &#8212;&#160;for instance, calculating &ldquo;previous,&rdquo; &ldquo;next,&rdquo; or &ldquo;up&rdquo; links for a given page. A special pagetree, <span class="stt">index.ptree</span>, is used by the project server to order the files in a dashboard. Pagetrees can also be used to define batches of files for certain operations, for instance <a href="http://docs.racket-lang.org/pollen/raco-pollen.html#%28part._raco_pollen_render%29" data-pltdoc="x"><span class="RktSym">raco</span><span class="stt"> </span><span class="RktSym">pollen</span><span class="stt"> </span><span class="RktSym">render</span></a>. You might find other uses for them too.</p><h5>11.4.1<tt>&nbsp;</tt><a name="(part._.Making_pagetrees_with_a_source_file)"></a>Making pagetrees with a source file</h5><p>A pagetree source file either starts with <span class="RktMeta">#lang</span><span class="hspace">&nbsp;</span><span class="RktMeta"></span><a href="index.html" class="RktModLink" data-pltdoc="x"><span class="RktSym">pollen</span></a><span class="RktMeta"></span> and uses the <span class="stt">.ptree</span> extension, or starts with <span class="RktMeta">#lang</span><span class="hspace">&nbsp;</span><span class="RktMeta"></span><a href="File_formats.html#%28mod-path._pollen%2Fptree%29" class="RktModLink" data-pltdoc="x"><span class="RktSym">pollen/ptree</span></a><span class="RktMeta"></span> and then can have any file extension.</p><p>Unlike other Pollen source files, since the pagetree source is not rendered into an output format, the rest of the filename is up to you.</p><p>Here&rsquo;s a flat pagetree. Each line is considered a single pagenode (blank lines are ignored). Notice that no Pollen command syntax nor quoting is needed within the pagetree source:</p><div class="fileblock"><div class="SIntrapara"><div class="fileblock_filetitle"><span class="fileblock_filename"><span class="stt">"flat.ptree"</span></span></div></div><div class="SIntrapara"><div class="fileblock_filecontent"><div class="SIntrapara"><blockquote class="SCodeFlow"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktMeta">#lang</span><span class="hspace">&nbsp;</span><span class="RktMeta"></span><a href="index.html" class="RktModLink" data-pltdoc="x"><span class="RktSym">pollen</span></a><span class="RktMeta"></span></td></tr><tr><td><span class="RktMeta">&#160;</span></td></tr><tr><td><span class="RktMeta">index.html</span></td></tr><tr><td><span class="RktMeta">introduction.html</span></td></tr><tr><td><span class="RktMeta">main_argument.html</span></td></tr><tr><td><span class="RktMeta">conclusion.html</span></td></tr></table></blockquote></div></div></div></div><p>And here&rsquo;s the output in DrRacket:</p><blockquote class="SubFlow"><p><span class="RktVal"><span class="stt">'(pagetree-root index.html introduction.html main_argument.html conclusion.html)</span></span></p></blockquote><p>Keeping with usual Pollen policy, this is an <a href="http://docs.racket-lang.org/pollen/second-tutorial.html#%28part._.X-expressions%29" data-pltdoc="x">X-expression</a>. The <span class="RktSym">pagetree-root</span> is just an arbitrary tag that contains the pagetree.</p><p>Upgrading to a hierarchical pagetree is simple. The same basic rule applies &#8212;&#160;one pagenode per line. But this time, you add Pollen command syntax: a lozenge <span class="RktInBG"><span class="hspace"></span><span class="RktIn">&#9674;</span><span class="hspace"></span></span> in front of a pagenode marks it as the top of a nested list, and the sub-pagenodes of that list go between <span class="RktInBG"><span class="hspace"></span><span class="RktIn">{</span><span class="hspace"></span></span> curly braces <span class="RktInBG"><span class="hspace"></span><span class="RktIn">}</span><span class="hspace"></span></span>, like so:</p><div class="fileblock"><div class="SIntrapara"><div class="fileblock_filetitle"><span class="fileblock_filename"><span class="stt">"hierarchical.ptree"</span></span></div></div><div class="SIntrapara"><div class="fileblock_filecontent"><div class="SIntrapara"><blockquote class="SCodeFlow"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktMeta">#lang</span><span class="hspace">&nbsp;</span><span class="RktMeta"></span><a href="index.html" class="RktModLink" data-pltdoc="x"><span class="RktSym">pollen</span></a><span class="RktMeta"></span></td></tr><tr><td><span class="RktMeta">&#160;</span></td></tr><tr><td><span class="RktMeta">toc.html</span></td></tr><tr><td><span class="RktMeta">&#9674;</span><span class="RktSym">first-chapter.html</span><span class="RktPn">{</span><span class="RktMeta"></span></td></tr><tr><td><span class="RktMeta"></span><span class="hspace">&nbsp;&nbsp;&nbsp;&nbsp;</span><span class="RktMeta">foreword.html</span></td></tr><tr><td><span class="RktMeta"></span><span class="hspace">&nbsp;&nbsp;&nbsp;&nbsp;</span><span class="RktMeta">introduction.html</span><span class="RktPn">}</span><span class="RktMeta"></span></td></tr><tr><td><span class="RktMeta">&#9674;</span><span class="RktSym">second-chapter.html</span><span class="RktPn">{</span><span class="RktMeta"></span></td></tr><tr><td><span class="RktMeta"></span><span class="hspace">&nbsp;&nbsp;&nbsp;&nbsp;</span><span class="RktMeta">&#9674;</span><span class="RktSym">main-argument.html</span><span class="RktPn">{</span><span class="RktMeta"></span></td></tr><tr><td><span class="RktMeta"></span><span class="hspace">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</span><span class="RktMeta">facts.html</span></td></tr><tr><td><span class="RktMeta"></span><span class="hspace">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</span><span class="RktMeta">analysis.html</span><span class="RktPn">}</span><span class="RktMeta"></span></td></tr><tr><td><span class="RktMeta"></span><span class="hspace">&nbsp;&nbsp;&nbsp;&nbsp;</span><span class="RktMeta">conclusion.html</span><span class="RktPn">}</span><span class="RktMeta"></span></td></tr><tr><td><span class="RktMeta">bibliography.html</span></td></tr></table></blockquote></div></div></div></div><p>The output of our hierarchical pagetree:</p><blockquote class="SubFlow"><p><span class="RktVal"><span class="stt">'(pagetree-root toc.html (first-chapter.html foreword.html introduction.html) (second-chapter.html (main-argument.html facts.html analysis.html) conclusion.html) bibliography.html)</span></span></p></blockquote><p>One advantage of using a source file is that when you run it in DrRacket, it will automatically be checked using <span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._validate-pagetree%29%29" class="RktValLink" data-pltdoc="x">validate-pagetree</a></span>, which insures that every element in the pagetree meets <span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagenode~3f%29%29" class="RktValLink" data-pltdoc="x">pagenode?</a></span>, and that all the pagenodes are unique.</p><p>This pagetree has a duplicate pagenode, so it won&rsquo;t run:</p><div class="fileblock"><div class="SIntrapara"><div class="fileblock_filetitle"><span class="fileblock_filename"><span class="stt">"duplicate-pagenode.ptree"</span></span></div></div><div class="SIntrapara"><div class="fileblock_filecontent"><div class="SIntrapara"><blockquote class="SCodeFlow"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktMeta">#lang</span><span class="hspace">&nbsp;</span><span class="RktMeta"></span><a href="index.html" class="RktModLink" data-pltdoc="x"><span class="RktSym">pollen</span></a><span class="RktMeta"></span></td></tr><tr><td><span class="RktMeta">&#160;</span></td></tr><tr><td><span class="RktMeta">index.html</span></td></tr><tr><td><span class="RktMeta">introduction.html</span></td></tr><tr><td><span class="RktMeta">main_argument.html</span></td></tr><tr><td><span class="RktMeta">conclusion.html</span></td></tr><tr><td><span class="RktMeta">index.html</span></td></tr></table></blockquote></div></div></div></div><p>Instead, you&rsquo;ll get an error:</p><blockquote class="SubFlow"><p><span class="RktErr"><span class="stt">validate-pagetree: members-unique? failed because item isn&#8217;t unique: (index.html)</span></span></p></blockquote><p>Pagenodes can refer to files in subdirectories. Just write the pagenode as a path relative to the directory where the pagetree lives:</p><div class="fileblock"><div class="SIntrapara"><div class="fileblock_filetitle"><span class="fileblock_filename"><span class="stt">"flat.ptree"</span></span></div></div><div class="SIntrapara"><div class="fileblock_filecontent"><div class="SIntrapara"><blockquote class="SCodeFlow"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktMeta">#lang</span><span class="hspace">&nbsp;</span><span class="RktMeta"></span><a href="index.html" class="RktModLink" data-pltdoc="x"><span class="RktSym">pollen</span></a><span class="RktMeta"></span></td></tr><tr><td><span class="RktMeta">&#160;</span></td></tr><tr><td><span class="RktMeta">foreword.html</span></td></tr><tr><td><span class="RktMeta">&#9674;</span><span class="RktSym">facts-intro.html</span><span class="RktPn">{</span><span class="RktMeta"></span></td></tr><tr><td><span class="RktMeta"></span><span class="hspace">&nbsp;&nbsp;&nbsp;&nbsp;</span><span class="RktMeta">facts/brennan.html</span></td></tr><tr><td><span class="RktMeta"></span><span class="hspace">&nbsp;&nbsp;&nbsp;&nbsp;</span><span class="RktMeta">facts/dale.html</span></td></tr><tr><td><span class="RktMeta"></span><span class="RktPn">}</span><span class="RktMeta"></span></td></tr><tr><td><span class="RktMeta">&#9674;</span><span class="RktSym">analysis/intro.html</span><span class="RktPn">{</span><span class="RktMeta"></span></td></tr><tr><td><span class="RktMeta"></span><span class="hspace">&nbsp;&nbsp;&nbsp;&nbsp;</span><span class="RktMeta">analysis/fancy-sauce/part-1.html</span></td></tr><tr><td><span class="RktMeta"></span><span class="hspace">&nbsp;&nbsp;&nbsp;&nbsp;</span><span class="RktMeta">analysis/fancy-sauce/part-2.html</span></td></tr><tr><td><span class="RktMeta"></span><span class="RktPn">}</span><span class="RktMeta"></span></td></tr><tr><td><span class="RktMeta">conclusion.html</span></td></tr></table></blockquote></div></div></div></div><h5>11.4.2<tt>&nbsp;</tt><a name="(part._.Making_pagetrees_by_hand)"></a>Making pagetrees by hand</h5><p>Experienced programmers may want to know that because a pagetree is just an X-expression, you can synthesize a pagetree using any Pollen or Racket tools for making X-expressions. For example, here&rsquo;s some Racket code that generates the same pagetree as the <span class="stt">flat.ptree</span> source file above:</p><div class="fileblock"><div class="SIntrapara"><div class="fileblock_filetitle"><span class="fileblock_filename"><span class="stt">"make-flat-ptree.rkt"</span></span></div></div><div class="SIntrapara"><div class="fileblock_filecontent"><div class="SIntrapara"><blockquote class="SCodeFlow"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktMeta">#lang</span><span class="hspace">&nbsp;</span><span class="RktMeta"></span><a href="http://docs.racket-lang.org/reference/index.html" class="RktModLink" data-pltdoc="x"><span class="RktSym">racket</span></a><span class="RktMeta"></span></td></tr><tr><td><span class="RktMeta"></span><span class="RktPn">(</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/require.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._require%29%29" class="RktStxLink" data-pltdoc="x">require</a></span><span class="RktMeta"></span><span class="hspace">&nbsp;</span><span class="RktMeta"></span><span class="RktSym">pollen/pagetree</span><span class="RktPn">)</span><span class="RktMeta"></span></td></tr><tr><td><span class="RktMeta"></span><span class="RktPn">(</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/define.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._define%29%29" class="RktStxLink" data-pltdoc="x">define</a></span><span class="RktMeta"></span><span class="hspace">&nbsp;</span><span class="RktMeta"></span><span class="RktSym">node-names</span><span class="RktMeta"></span><span class="hspace">&nbsp;</span><span class="RktMeta"></span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/quote.html#%28form._%28%28quote._~23~25kernel%29._quote%29%29" class="RktStxLink" data-pltdoc="x">'</a></span><span class="RktPn">(</span><span class="RktSym">index</span><span class="RktMeta"></span><span class="hspace">&nbsp;</span><span class="RktMeta"></span><span class="RktSym">introduction</span><span class="RktMeta"></span><span class="hspace">&nbsp;</span><span class="RktMeta"></span><span class="RktSym">main_argument</span><span class="RktMeta"></span><span class="hspace">&nbsp;</span><span class="RktMeta"></span><span class="RktSym">conclusion</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktMeta"></span></td></tr><tr><td><span class="RktMeta"></span><span class="RktPn">(</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/define.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._define%29%29" class="RktStxLink" data-pltdoc="x">define</a></span><span class="RktMeta"></span><span class="hspace">&nbsp;</span><span class="RktMeta"></span><span class="RktSym">pt</span><span class="RktMeta"></span><span class="hspace">&nbsp;</span><span class="RktMeta"></span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/quasiquote.html#%28form._%28%28lib._racket%2Fprivate%2Fletstx-scheme..rkt%29._quasiquote%29%29" class="RktStxLink" data-pltdoc="x">`</a></span><span class="RktPn">(</span><span class="RktSym">pagetree-root</span><span class="RktMeta"></span></td></tr><tr><td><span class="RktMeta"></span><span class="hspace">&nbsp;&nbsp;</span><span class="RktMeta"></span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/quasiquote.html#%28form._%28%28quote._~23~25kernel%29._unquote-splicing%29%29" class="RktStxLink" data-pltdoc="x">,@</a></span><span class="RktPn">(</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/pairs.html#%28def._%28%28lib._racket%2Fprivate%2Fmap..rkt%29._map%29%29" class="RktValLink" data-pltdoc="x">map</a></span><span class="RktMeta"></span><span class="hspace">&nbsp;</span><span class="RktMeta"></span><span class="RktPn">(</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/lambda.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._~ce~bb%29%29" class="RktStxLink" data-pltdoc="x">&#955;</a></span><span class="RktPn">(</span><span class="RktSym">n</span><span class="RktPn">)</span><span class="RktMeta"></span><span class="hspace">&nbsp;</span><span class="RktMeta"></span><span class="RktPn">(</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/symbols.html#%28def._%28%28quote._~23~25kernel%29._string-~3esymbol%29%29" class="RktValLink" data-pltdoc="x">string-&gt;symbol</a></span><span class="RktMeta"></span><span class="hspace">&nbsp;</span><span class="RktMeta"></span><span class="RktPn">(</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/Writing.html#%28def._%28%28quote._~23~25kernel%29._format%29%29" class="RktValLink" data-pltdoc="x">format</a></span><span class="RktMeta"></span><span class="hspace">&nbsp;</span><span class="RktMeta"></span><span class="RktVal">"~a.html"</span><span class="RktMeta"></span><span class="hspace">&nbsp;</span><span class="RktMeta"></span><span class="RktSym">n</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktMeta"></span><span class="hspace">&nbsp;</span><span class="RktMeta"></span><span class="RktSym">node-names</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktMeta"></span></td></tr><tr><td><span class="RktMeta"></span><span class="RktPn">(</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/if.html#%28form._%28%28quote._~23~25kernel%29._if%29%29" class="RktStxLink" data-pltdoc="x">if</a></span><span class="RktMeta"></span><span class="hspace">&nbsp;</span><span class="RktMeta"></span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagetree~3f%29%29" class="RktValLink" data-pltdoc="x">pagetree?</a></span><span class="RktMeta"></span><span class="hspace">&nbsp;</span><span class="RktMeta"></span><span class="RktSym">pt</span><span class="RktPn">)</span><span class="RktMeta"></span><span class="hspace">&nbsp;</span><span class="RktMeta"></span><span class="RktSym">pt</span><span class="RktMeta"></span><span class="hspace">&nbsp;</span><span class="RktMeta"></span><span class="RktVal">"Oops,</span><span class="hspace">&nbsp;</span><span class="RktVal">not</span><span class="hspace">&nbsp;</span><span class="RktVal">a</span><span class="hspace">&nbsp;</span><span class="RktVal">pagetree"</span><span class="RktPn">)</span><span class="RktMeta"></span></td></tr></table></blockquote></div></div></div></div><p>Note that you need to take more care when building a pagetree by hand. Pagenodes are symbols, not strings, thus the use of <span class="RktSym"><a href="http://docs.racket-lang.org/reference/symbols.html#%28def._%28%28quote._~23~25kernel%29._string-~3esymbol%29%29" class="RktValLink" data-pltdoc="x">string-&gt;symbol</a></span> is mandatory. One benefit of using a pagetree source file is that it takes care of this housekeeping for you.</p><h5>11.4.3<tt>&nbsp;</tt><a name="(part._.Using_pagetrees_for_navigation)"></a>Using pagetrees for navigation</h5><p>Typically you&rsquo;ll call the pagetree-navigation functions from inside templates, using the special variable <span class="RktSym">here</span> as the starting point. For more on this technique, see <a href="second-tutorial.html#%28part._tutorial-2._.Pagetree_navigation%29" data-pltdoc="x">Pagetree navigation</a>.</p><h5>11.4.4<tt>&nbsp;</tt><a name="(part._.Using_index_ptree_in_the_dashboard)"></a>Using <span class="stt">index.ptree</span> in the dashboard</h5><p>When you&rsquo;re using the project server to view the files in a directory, the server will first look for a file called <span class="stt">index.ptree</span>. If it finds this pagetree file, it will use it to build the dashboard. If not, then it will synthesize a pagetree using a directory listing. For more on this technique, see <a href="http://docs.racket-lang.org/pollen/first-tutorial.html#%28part._.Using_the_dashboard%29" data-pltdoc="x">Using the dashboard</a>.</p><h5>11.4.5<tt>&nbsp;</tt><a name="(part._.Using_pagetrees_with_raco_pollen_render)"></a>Using pagetrees with <span class="stt">raco pollen render</span></h5><p>The <span class="stt">raco pollen render</span> command is used to regenerate an output file from its source. If you pass a pagetree to <span class="stt">raco pollen render</span>, it will automatically render each file listed in the pagetree.</p><p>For instance, many projects have auxiliary pages that don&rsquo;t really belong in the main navigational flow. You can collect these pages in a separate pagetree:</p><div class="fileblock"><div class="SIntrapara"><div class="fileblock_filetitle"><span class="fileblock_filename"><span class="stt">"utility.ptree"</span></span></div></div><div class="SIntrapara"><div class="fileblock_filecontent"><div class="SIntrapara"><blockquote class="SCodeFlow"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktMeta">#lang</span><span class="hspace">&nbsp;</span><span class="RktMeta"></span><a href="index.html" class="RktModLink" data-pltdoc="x"><span class="RktSym">pollen</span></a><span class="RktMeta"></span></td></tr><tr><td><span class="RktMeta">&#160;</span></td></tr><tr><td><span class="RktMeta">404-error.html</span></td></tr><tr><td><span class="RktMeta">terms-of-service.html</span></td></tr><tr><td><span class="RktMeta">webmaster.html</span></td></tr><tr><td><span class="RktMeta"></span><span class="RktPn">[</span><span class="RktMeta">...</span><span class="hspace">&nbsp;</span><span class="RktMeta">and</span><span class="hspace">&nbsp;</span><span class="RktMeta">so</span><span class="hspace">&nbsp;</span><span class="RktMeta">on</span><span class="RktPn">]</span><span class="RktMeta"></span></td></tr></table></blockquote></div></div></div></div><p>Thus, when you&rsquo;re using pagetree-navigation functions within a template, you can use your main pagetree, and restrict the navigation to the main editorial content. But when you render the project, you can pass both pagetrees to <span class="stt">raco pollen render</span>.</p><p>For more on this technique, see <a href="http://docs.racket-lang.org/pollen/raco-pollen.html#%28part._raco_pollen_render%29" data-pltdoc="x"><span class="RktSym">raco</span><span class="stt"> </span><span class="RktSym">pollen</span><span class="stt"> </span><span class="RktSym">render</span></a>.</p><h5>11.4.6<tt>&nbsp;</tt><a name="(part._.Functions)"></a>Functions</h5><h5>11.4.6.1<tt>&nbsp;</tt><a name="(part._.Predicates___validation)"></a>Predicates &amp; validation</h5><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._pollen/pagetree..rkt)._pagetree~3f))"></a><span title="Provided from: pollen/pagetree | Package: pollen"><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagetree~3f%29%29" class="RktValDef RktValLink" data-pltdoc="x">pagetree?</a></span></span><span class="hspace">&nbsp;</span><span class="RktVar">possible-pagetree</span><span class="RktPn">)</span><span class="hspace">&nbsp;</span>&rarr;<span class="hspace">&nbsp;</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/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">&nbsp;&nbsp;</span><span class="RktVar">possible-pagetree</span><span class="hspace">&nbsp;</span>:<span class="hspace">&nbsp;</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/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">Test whether <span class="RktVar">possible-pagetree</span> is a valid pagetree. It must be a <span class="RktSym"><a href="http://docs.racket-lang.org/txexpr/index.html#%28def._%28%28lib._txexpr%2Fmain..rkt%29._txexpr~3f%29%29" class="RktValLink" data-pltdoc="x">txexpr?</a></span> where all elements are <span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagenode~3f%29%29" class="RktValLink" data-pltdoc="x">pagenode?</a></span>, and each is unique within <span class="RktVar">possible-pagetree</span> (not counting the root node).</div></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><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagetree~3f%29%29" class="RktValLink" data-pltdoc="x">pagetree?</a></span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">(</span><span class="RktVal">root</span><span class="hspace">&nbsp;</span><span class="RktVal">index.html</span><span class="RktVal">)</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">#t</span></p></td></tr><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagetree~3f%29%29" class="RktValLink" data-pltdoc="x">pagetree?</a></span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">(</span><span class="RktVal">root</span><span class="hspace">&nbsp;</span><span class="RktVal">duplicate.html</span><span class="hspace">&nbsp;</span><span class="RktVal">duplicate.html</span><span class="RktVal">)</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">#f</span></p></td></tr><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagetree~3f%29%29" class="RktValLink" data-pltdoc="x">pagetree?</a></span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">(</span><span class="RktVal">root</span><span class="hspace">&nbsp;</span><span class="RktVal">index.html</span><span class="hspace">&nbsp;</span><span class="RktVal">"string.html"</span><span class="RktVal">)</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">#f</span></p></td></tr><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/define.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._define%29%29" class="RktStxLink" data-pltdoc="x">define</a></span><span class="hspace">&nbsp;</span><span class="RktSym">nested-ptree</span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">(</span><span class="RktVal">root</span><span class="hspace">&nbsp;</span><span class="RktVal">1.html</span><span class="hspace">&nbsp;</span><span class="RktVal">2.html</span><span class="hspace">&nbsp;</span><span class="RktVal">(</span><span class="RktVal">3.html</span><span class="hspace">&nbsp;</span><span class="RktVal">3a.html</span><span class="hspace">&nbsp;</span><span class="RktVal">3b.html</span><span class="RktVal">)</span><span class="RktVal">)</span><span class="RktPn">)</span></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"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagetree~3f%29%29" class="RktValLink" data-pltdoc="x">pagetree?</a></span><span class="hspace">&nbsp;</span><span class="RktSym">nested-ptree</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">#t</span></p></td></tr><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagetree~3f%29%29" class="RktValLink" data-pltdoc="x">pagetree?</a></span><span class="hspace">&nbsp;</span><span class="RktVal">`</span><span class="RktVal">(</span><span class="RktVal">root</span><span class="hspace">&nbsp;</span><span class="RktVal">index.html</span><span class="hspace">&nbsp;</span><span class="RktRdr">,</span><span class="RktSym">nested-ptree</span><span class="hspace">&nbsp;</span><span class="RktVal">(</span><span class="RktVal">subsection.html</span><span class="hspace">&nbsp;</span><span class="RktVal">more.html</span><span class="RktVal">)</span><span class="RktVal">)</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">#t</span></p></td></tr><tr><td><span class="RktCmt">;</span><span class="RktCmt">&nbsp;</span><span class="RktCmt">Nesting a subtree twice creates duplication</span></td></tr><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagetree~3f%29%29" class="RktValLink" data-pltdoc="x">pagetree?</a></span><span class="hspace">&nbsp;</span><span class="RktVal">`</span><span class="RktVal">(</span><span class="RktVal">root</span><span class="hspace">&nbsp;</span><span class="RktVal">index.html</span><span class="hspace">&nbsp;</span><span class="RktRdr">,</span><span class="RktSym">nested-ptree</span><span class="hspace">&nbsp;</span><span class="RktVal">(</span><span class="RktVal">subsection.html</span><span class="hspace">&nbsp;</span><span class="RktRdr">,</span><span class="RktSym">nested-ptree</span><span class="RktVal">)</span><span class="RktVal">)</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">#f</span></p></td></tr></table></blockquote></td></tr></table></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._pollen/pagetree..rkt)._validate-pagetree))"></a><span title="Provided from: pollen/pagetree | Package: pollen"><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._validate-pagetree%29%29" class="RktValDef RktValLink" data-pltdoc="x">validate-pagetree</a></span></span><span class="hspace">&nbsp;</span><span class="RktVar">possible-pagetree</span><span class="RktPn">)</span><span class="hspace">&nbsp;</span>&rarr;<span class="hspace">&nbsp;</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagetree~3f%29%29" class="RktValLink" data-pltdoc="x">pagetree?</a></span></p></blockquote></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktVar">possible-pagetree</span><span class="hspace">&nbsp;</span>:<span class="hspace">&nbsp;</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/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">Like <span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagetree~3f%29%29" class="RktValLink" data-pltdoc="x">pagetree?</a></span>, but raises a descriptive error if <span class="RktVar">possible-pagetree</span> is invalid, and otherwise returns <span class="RktVar">possible-pagetree</span> itself.</div></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><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._validate-pagetree%29%29" class="RktValLink" data-pltdoc="x">validate-pagetree</a></span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">(</span><span class="RktVal">root</span><span class="hspace">&nbsp;</span><span class="RktVal">(</span><span class="RktVal">mama.html</span><span class="hspace">&nbsp;</span><span class="RktVal">son.html</span><span class="hspace">&nbsp;</span><span class="RktVal">daughter.html</span><span class="RktVal">)</span><span class="hspace">&nbsp;</span><span class="RktVal">uncle.html</span><span class="RktVal">)</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">'(root (mama.html son.html daughter.html) uncle.html)</span></p></td></tr><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._validate-pagetree%29%29" class="RktValLink" data-pltdoc="x">validate-pagetree</a></span><span class="hspace">&nbsp;</span><span class="RktVal">`</span><span class="RktVal">(</span><span class="RktVal">root</span><span class="hspace">&nbsp;</span><span class="RktVal">(</span><span class="RktRdr">,</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/generic-numbers.html#%28def._%28%28quote._~23~25kernel%29._%2B%29%29" class="RktValLink" data-pltdoc="x">+</a></span><span class="hspace">&nbsp;</span><span class="RktVal">son.html</span><span class="hspace">&nbsp;</span><span class="RktVal">daughter.html</span><span class="RktVal">)</span><span class="hspace">&nbsp;</span><span class="RktVal">uncle.html</span><span class="RktVal">)</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">#f</span></p></td></tr><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._validate-pagetree%29%29" class="RktValLink" data-pltdoc="x">validate-pagetree</a></span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">(</span><span class="RktVal">root</span><span class="hspace">&nbsp;</span><span class="RktVal">(</span><span class="RktVal">mama.html</span><span class="hspace">&nbsp;</span><span class="RktVal">son.html</span><span class="hspace">&nbsp;</span><span class="RktVal">son.html</span><span class="RktVal">)</span><span class="hspace">&nbsp;</span><span class="RktVal">mama.html</span><span class="RktVal">)</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktErr">validate-pagetree: members-unique? failed because items</span></p></td></tr><tr><td><p><span class="RktErr">aren&#8217;t unique: (son.html mama.html)</span></p></td></tr></table></blockquote></td></tr></table></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._pollen/pagetree..rkt)._pagenode~3f))"></a><span title="Provided from: pollen/pagetree | Package: pollen"><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagenode~3f%29%29" class="RktValDef RktValLink" data-pltdoc="x">pagenode?</a></span></span><span class="hspace">&nbsp;</span><span class="RktVar">possible-pagenode</span><span class="RktPn">)</span><span class="hspace">&nbsp;</span>&rarr;<span class="hspace">&nbsp;</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/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">&nbsp;&nbsp;</span><span class="RktVar">possible-pagenode</span><span class="hspace">&nbsp;</span>:<span class="hspace">&nbsp;</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/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">Test whether <span class="RktVar">possible-pagenode</span> is a valid pagenode. A pagenode can be any <span class="RktSym"><a href="http://docs.racket-lang.org/reference/symbols.html#%28def._%28%28quote._~23~25kernel%29._symbol~3f%29%29" class="RktValLink" data-pltdoc="x">symbol?</a></span> that is not <span class="RktSym"><a href="Decode.html#%28def._%28%28lib._pollen%2Fdecode..rkt%29._whitespace%2Fnbsp~3f%29%29" class="RktValLink" data-pltdoc="x">whitespace/nbsp?</a></span> Every leaf of a pagetree is a pagenode. In practice, your pagenodes will likely be names of output files.</div></p><blockquote class="refpara"><blockquote class="refcolumn"><blockquote class="refcontent"><p>Pagenodes are symbols (rather than strings) so that pagetrees will be valid tagged X-expressions, which is a more convenient format for validation &amp; processing.</p></blockquote></blockquote></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><span class="RktCmt">;</span><span class="RktCmt">&nbsp;</span><span class="RktCmt">Three symbols, the third one annoying but valid</span></td></tr><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/pairs.html#%28def._%28%28lib._racket%2Fprivate%2Fmap..rkt%29._map%29%29" class="RktValLink" data-pltdoc="x">map</a></span><span class="hspace">&nbsp;</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagenode~3f%29%29" class="RktValLink" data-pltdoc="x">pagenode?</a></span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">(</span><span class="RktVal">symbol</span><span class="hspace">&nbsp;</span><span class="RktVal">index.html</span><span class="hspace">&nbsp;</span><span class="RktVal">|</span><span class="hspace">&nbsp;&nbsp;&nbsp;</span><span class="RktVal">silly</span><span class="hspace">&nbsp;&nbsp;&nbsp;</span><span class="RktVal">|</span><span class="RktVal">)</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">'(#t #t #t)</span></p></td></tr><tr><td><span class="RktCmt">;</span><span class="RktCmt">&nbsp;</span><span class="RktCmt">A number, a string, a txexpr, and a whitespace symbol</span></td></tr><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/pairs.html#%28def._%28%28lib._racket%2Fprivate%2Fmap..rkt%29._map%29%29" class="RktValLink" data-pltdoc="x">map</a></span><span class="hspace">&nbsp;</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagenode~3f%29%29" class="RktValLink" data-pltdoc="x">pagenode?</a></span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">(</span><span class="RktVal">9.999</span><span class="hspace">&nbsp;</span><span class="RktVal">"index.html"</span><span class="hspace">&nbsp;</span><span class="RktVal">(</span><span class="RktVal">p</span><span class="hspace">&nbsp;</span><span class="RktVal">"Hello"</span><span class="RktVal">)</span><span class="hspace">&nbsp;</span><span class="RktVal">|</span><span class="hspace">&nbsp;&nbsp;&nbsp;&nbsp;</span><span class="RktVal">|</span><span class="RktVal">)</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">'(#f #f #f #f)</span></p></td></tr></table></blockquote></td></tr></table></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._pollen/pagetree..rkt)._pagenodeish~3f))"></a><span title="Provided from: pollen/pagetree | Package: pollen"><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagenodeish~3f%29%29" class="RktValDef RktValLink" data-pltdoc="x">pagenodeish?</a></span></span><span class="hspace">&nbsp;</span><span class="RktVar">v</span><span class="RktPn">)</span><span class="hspace">&nbsp;</span>&rarr;<span class="hspace">&nbsp;</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/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">&nbsp;&nbsp;</span><span class="RktVar">v</span><span class="hspace">&nbsp;</span>:<span class="hspace">&nbsp;</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/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">Return <span class="RktVal">#t</span> if <span class="RktVar">v</span> can be converted with <span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._-~3epagenode%29%29" class="RktValLink" data-pltdoc="x"><span class="nobreak">-&gt;</span>pagenode</a></span>.</div></p><p><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><p>Example:</p></td></tr><tr><td><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://docs.racket-lang.org/reference/pairs.html#%28def._%28%28lib._racket%2Fprivate%2Fmap..rkt%29._map%29%29" class="RktValLink" data-pltdoc="x">map</a></span><span class="hspace">&nbsp;</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagenodeish~3f%29%29" class="RktValLink" data-pltdoc="x">pagenodeish?</a></span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">(</span><span class="RktVal">9.999</span><span class="hspace">&nbsp;</span><span class="RktVal">"index.html"</span><span class="hspace">&nbsp;</span><span class="RktVal">|</span><span class="hspace">&nbsp;&nbsp;&nbsp;&nbsp;</span><span class="RktVal">|</span><span class="RktVal">)</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">'(#t #t #f)</span></p></td></tr></table></blockquote></td></tr></table></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._pollen/pagetree..rkt)._-~3epagenode))"></a><span title="Provided from: pollen/pagetree | Package: pollen"><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._-~3epagenode%29%29" class="RktValDef RktValLink" data-pltdoc="x"><span class="nobreak">-&gt;</span>pagenode</a></span></span><span class="hspace">&nbsp;</span><span class="RktVar">v</span><span class="RktPn">)</span><span class="hspace">&nbsp;</span>&rarr;<span class="hspace">&nbsp;</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagenode~3f%29%29" class="RktValLink" data-pltdoc="x">pagenode?</a></span></p></blockquote></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktVar">v</span><span class="hspace">&nbsp;</span>:<span class="hspace">&nbsp;</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagenodeish~3f%29%29" class="RktValLink" data-pltdoc="x">pagenodeish?</a></span></td></tr></table></blockquote></div><div class="SIntrapara">Convert <span class="RktVar">v</span> to a pagenode.</div></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><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/pairs.html#%28def._%28%28lib._racket%2Fprivate%2Fmap..rkt%29._map%29%29" class="RktValLink" data-pltdoc="x">map</a></span><span class="hspace">&nbsp;</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagenodeish~3f%29%29" class="RktValLink" data-pltdoc="x">pagenodeish?</a></span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">(</span><span class="RktVal">symbol</span><span class="hspace">&nbsp;</span><span class="RktVal">9.999</span><span class="hspace">&nbsp;</span><span class="RktVal">"index.html"</span><span class="hspace">&nbsp;</span><span class="RktVal">|</span><span class="hspace">&nbsp;&nbsp;</span><span class="RktVal">silly</span><span class="hspace">&nbsp;&nbsp;</span><span class="RktVal">|</span><span class="RktVal">)</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">'(#t #t #t #t)</span></p></td></tr><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/pairs.html#%28def._%28%28lib._racket%2Fprivate%2Fmap..rkt%29._map%29%29" class="RktValLink" data-pltdoc="x">map</a></span><span class="hspace">&nbsp;</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._-~3epagenode%29%29" class="RktValLink" data-pltdoc="x"><span class="nobreak">-&gt;</span>pagenode</a></span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">(</span><span class="RktVal">symbol</span><span class="hspace">&nbsp;</span><span class="RktVal">9.999</span><span class="hspace">&nbsp;</span><span class="RktVal">"index.html"</span><span class="hspace">&nbsp;</span><span class="RktVal">|</span><span class="hspace">&nbsp;&nbsp;</span><span class="RktVal">silly</span><span class="hspace">&nbsp;&nbsp;</span><span class="RktVal">|</span><span class="RktVal">)</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">'(symbol |9.999| index.html |</span><span class="hspace">&nbsp;&nbsp;</span><span class="RktRes">silly</span><span class="hspace">&nbsp;&nbsp;</span><span class="RktRes">|)</span></p></td></tr></table></blockquote></td></tr></table></p><h5>11.4.6.2<tt>&nbsp;</tt><a name="(part._.Navigation)"></a>Navigation</h5><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>parameter</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((lib._pollen/pagetree..rkt)._current-pagetree))"></a><span title="Provided from: pollen/pagetree | Package: pollen"><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._current-pagetree%29%29" class="RktValDef RktValLink" data-pltdoc="x">current-pagetree</a></span></span><span class="RktPn"></span><span class="RktPn">)</span><span class="hspace">&nbsp;</span>&rarr;<span class="hspace">&nbsp;</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagetree~3f%29%29" class="RktValLink" data-pltdoc="x">pagetree?</a></span></p></blockquote></td></tr><tr><td><span class="RktPn">(</span><span title="Provided from: pollen/pagetree | Package: pollen"><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._current-pagetree%29%29" class="RktValDef RktValLink" data-pltdoc="x">current-pagetree</a></span></span><span class="hspace">&nbsp;</span><span class="RktVar">pagetree</span><span class="RktPn">)</span><span class="hspace">&nbsp;</span>&rarr;<span class="hspace">&nbsp;</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/void.html#%28def._%28%28quote._~23~25kernel%29._void~3f%29%29" class="RktValLink" data-pltdoc="x">void?</a></span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktVar">pagetree</span><span class="hspace">&nbsp;</span>:<span class="hspace">&nbsp;</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagetree~3f%29%29" class="RktValLink" data-pltdoc="x">pagetree?</a></span></td></tr></table></blockquote></div><div class="SIntrapara">A parameter that defines the default pagetree used by pagetree navigation functions (e.g., <span class="RktSym">parent-pagenode</span>, <span class="RktSym">chidren</span>, et al.) if another is not explicitly specified. Initialized to <span class="RktVal">#f</span>.</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._((lib._pollen/pagetree..rkt)._parent))"></a><span title="Provided from: pollen/pagetree | Package: pollen"><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._parent%29%29" class="RktValDef RktValLink" data-pltdoc="x">parent</a></span></span><span class="hspace">&nbsp;</span><span class="RktVar">p</span><span class="hspace">&nbsp;</span>[<span class="RktVar">pagetree</span>]<span class="RktPn">)</span><span class="hspace">&nbsp;</span>&rarr;<span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace">&nbsp;</span><span class="RktVal">#f</span><span class="hspace">&nbsp;</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagenode~3f%29%29" class="RktValLink" data-pltdoc="x">pagenode?</a></span><span class="RktPn">)</span></p></blockquote></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktVar">p</span><span class="hspace">&nbsp;</span>:<span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace">&nbsp;</span><span class="RktVal">#f</span><span class="hspace">&nbsp;</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagenodeish~3f%29%29" class="RktValLink" data-pltdoc="x">pagenodeish?</a></span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktVar">pagetree</span><span class="hspace">&nbsp;</span>:<span class="hspace">&nbsp;</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagetree~3f%29%29" class="RktValLink" data-pltdoc="x">pagetree?</a></span><span class="hspace">&nbsp;</span>=<span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._current-pagetree%29%29" class="RktValLink" data-pltdoc="x">current-pagetree</a></span><span class="RktPn">)</span></td></tr></table></blockquote></div><div class="SIntrapara">Find the parent pagenode of <span class="RktVar">p</span> within <span class="RktVar">pagetree</span>. Return <span class="RktVal">#f</span> if there isn&rsquo;t one.</div></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><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._current-pagetree%29%29" class="RktValLink" data-pltdoc="x">current-pagetree</a></span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">(</span><span class="RktVal">root</span><span class="hspace">&nbsp;</span><span class="RktVal">(</span><span class="RktVal">mama.html</span><span class="hspace">&nbsp;</span><span class="RktVal">son.html</span><span class="hspace">&nbsp;</span><span class="RktVal">daughter.html</span><span class="RktVal">)</span><span class="hspace">&nbsp;</span><span class="RktVal">uncle.html</span><span class="RktVal">)</span><span class="RktPn">)</span></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"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._parent%29%29" class="RktValLink" data-pltdoc="x">parent</a></span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">son.html</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">'mama.html</span></p></td></tr><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._parent%29%29" class="RktValLink" data-pltdoc="x">parent</a></span><span class="hspace">&nbsp;</span><span class="RktVal">"mama.html"</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">'root</span></p></td></tr><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._parent%29%29" class="RktValLink" data-pltdoc="x">parent</a></span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._parent%29%29" class="RktValLink" data-pltdoc="x">parent</a></span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">son.html</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">'root</span></p></td></tr><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._parent%29%29" class="RktValLink" data-pltdoc="x">parent</a></span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._parent%29%29" class="RktValLink" data-pltdoc="x">parent</a></span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._parent%29%29" class="RktValLink" data-pltdoc="x">parent</a></span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">son.html</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">#f</span></p></td></tr></table></blockquote></td></tr></table></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._pollen/pagetree..rkt)._children))"></a><span title="Provided from: pollen/pagetree | Package: pollen"><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._children%29%29" class="RktValDef RktValLink" data-pltdoc="x">children</a></span></span><span class="hspace">&nbsp;</span><span class="RktVar">p</span><span class="hspace">&nbsp;</span>[<span class="RktVar">pagetree</span>]<span class="RktPn">)</span><span class="hspace">&nbsp;</span>&rarr;<span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace">&nbsp;</span><span class="RktVal">#f</span><span class="hspace">&nbsp;</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagenode~3f%29%29" class="RktValLink" data-pltdoc="x">pagenode?</a></span><span class="RktPn">)</span></p></blockquote></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktVar">p</span><span class="hspace">&nbsp;</span>:<span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace">&nbsp;</span><span class="RktVal">#f</span><span class="hspace">&nbsp;</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagenodeish~3f%29%29" class="RktValLink" data-pltdoc="x">pagenodeish?</a></span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktVar">pagetree</span><span class="hspace">&nbsp;</span>:<span class="hspace">&nbsp;</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagetree~3f%29%29" class="RktValLink" data-pltdoc="x">pagetree?</a></span><span class="hspace">&nbsp;</span>=<span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._current-pagetree%29%29" class="RktValLink" data-pltdoc="x">current-pagetree</a></span><span class="RktPn">)</span></td></tr></table></blockquote></div><div class="SIntrapara">Find the child pagenodes of <span class="RktVar">p</span> within <span class="RktVar">pagetree</span>. Return <span class="RktVal">#f</span> if there aren&rsquo;t any.</div></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><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._current-pagetree%29%29" class="RktValLink" data-pltdoc="x">current-pagetree</a></span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">(</span><span class="RktVal">root</span><span class="hspace">&nbsp;</span><span class="RktVal">(</span><span class="RktVal">mama.html</span><span class="hspace">&nbsp;</span><span class="RktVal">son.html</span><span class="hspace">&nbsp;</span><span class="RktVal">daughter.html</span><span class="RktVal">)</span><span class="hspace">&nbsp;</span><span class="RktVal">uncle.html</span><span class="RktVal">)</span><span class="RktPn">)</span></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"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._children%29%29" class="RktValLink" data-pltdoc="x">children</a></span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">mama.html</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">'(son.html daughter.html)</span></p></td></tr><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._children%29%29" class="RktValLink" data-pltdoc="x">children</a></span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">uncle.html</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">#f</span></p></td></tr><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._children%29%29" class="RktValLink" data-pltdoc="x">children</a></span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">root</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">'(mama.html uncle.html)</span></p></td></tr><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/pairs.html#%28def._%28%28lib._racket%2Fprivate%2Fmap..rkt%29._map%29%29" class="RktValLink" data-pltdoc="x">map</a></span><span class="hspace">&nbsp;</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._children%29%29" class="RktValLink" data-pltdoc="x">children</a></span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._children%29%29" class="RktValLink" data-pltdoc="x">children</a></span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">root</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">'((son.html daughter.html) #f)</span></p></td></tr></table></blockquote></td></tr></table></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._pollen/pagetree..rkt)._siblings))"></a><span title="Provided from: pollen/pagetree | Package: pollen"><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._siblings%29%29" class="RktValDef RktValLink" data-pltdoc="x">siblings</a></span></span><span class="hspace">&nbsp;</span><span class="RktVar">p</span><span class="hspace">&nbsp;</span>[<span class="RktVar">pagetree</span>]<span class="RktPn">)</span><span class="hspace">&nbsp;</span>&rarr;<span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace">&nbsp;</span><span class="RktVal">#f</span><span class="hspace">&nbsp;</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagenode~3f%29%29" class="RktValLink" data-pltdoc="x">pagenode?</a></span><span class="RktPn">)</span></p></blockquote></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktVar">p</span><span class="hspace">&nbsp;</span>:<span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace">&nbsp;</span><span class="RktVal">#f</span><span class="hspace">&nbsp;</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagenodeish~3f%29%29" class="RktValLink" data-pltdoc="x">pagenodeish?</a></span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktVar">pagetree</span><span class="hspace">&nbsp;</span>:<span class="hspace">&nbsp;</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagetree~3f%29%29" class="RktValLink" data-pltdoc="x">pagetree?</a></span><span class="hspace">&nbsp;</span>=<span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._current-pagetree%29%29" class="RktValLink" data-pltdoc="x">current-pagetree</a></span><span class="RktPn">)</span></td></tr></table></blockquote></div><div class="SIntrapara">Find the sibling pagenodes of <span class="RktVar">p</span> within <span class="RktVar">pagetree</span>. The list will include <span class="RktVar">p</span> itself. But the function will still return <span class="RktVal">#f</span> if <span class="RktVar">pagetree</span> is <span class="RktVal">#f</span>.</div></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><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._current-pagetree%29%29" class="RktValLink" data-pltdoc="x">current-pagetree</a></span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">(</span><span class="RktVal">root</span><span class="hspace">&nbsp;</span><span class="RktVal">(</span><span class="RktVal">mama.html</span><span class="hspace">&nbsp;</span><span class="RktVal">son.html</span><span class="hspace">&nbsp;</span><span class="RktVal">daughter.html</span><span class="RktVal">)</span><span class="hspace">&nbsp;</span><span class="RktVal">uncle.html</span><span class="RktVal">)</span><span class="RktPn">)</span></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"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._siblings%29%29" class="RktValLink" data-pltdoc="x">siblings</a></span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">son.html</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">'(son.html daughter.html)</span></p></td></tr><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._siblings%29%29" class="RktValLink" data-pltdoc="x">siblings</a></span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">daughter.html</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">'(son.html daughter.html)</span></p></td></tr><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._siblings%29%29" class="RktValLink" data-pltdoc="x">siblings</a></span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">mama.html</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">'(mama.html uncle.html)</span></p></td></tr></table></blockquote></td></tr></table></p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><table cellspacing="0" cellpadding="0" class="together"><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._pollen/pagetree..rkt)._previous))"></a><span title="Provided from: pollen/pagetree | Package: pollen"><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._previous%29%29" class="RktValDef RktValLink" data-pltdoc="x">previous</a></span></span><span class="hspace">&nbsp;</span><span class="RktVar">p</span><span class="hspace">&nbsp;</span>[<span class="RktVar">pagetree</span>]<span class="RktPn">)</span><span class="hspace">&nbsp;</span>&rarr;<span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace">&nbsp;</span><span class="RktVal">#f</span><span class="hspace">&nbsp;</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagenode~3f%29%29" class="RktValLink" data-pltdoc="x">pagenode?</a></span><span class="RktPn">)</span></p></blockquote></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktVar">p</span><span class="hspace">&nbsp;</span>:<span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace">&nbsp;</span><span class="RktVal">#f</span><span class="hspace">&nbsp;</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagenodeish~3f%29%29" class="RktValLink" data-pltdoc="x">pagenodeish?</a></span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktVar">pagetree</span><span class="hspace">&nbsp;</span>:<span class="hspace">&nbsp;</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagetree~3f%29%29" class="RktValLink" data-pltdoc="x">pagetree?</a></span><span class="hspace">&nbsp;</span>=<span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._current-pagetree%29%29" class="RktValLink" data-pltdoc="x">current-pagetree</a></span><span class="RktPn">)</span></td></tr></table></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="together"><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._pollen/pagetree..rkt)._previous*))"></a><span title="Provided from: pollen/pagetree | Package: pollen"><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._previous%2A%29%29" class="RktValDef RktValLink" data-pltdoc="x">previous*</a></span></span><span class="hspace">&nbsp;</span><span class="RktVar">p</span><span class="hspace">&nbsp;</span>[<span class="RktVar">pagetree</span>]<span class="RktPn">)</span><span class="hspace">&nbsp;</span>&rarr;<span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace">&nbsp;</span><span class="RktVal">#f</span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._listof%29%29" class="RktValLink" data-pltdoc="x">listof</a></span><span class="hspace">&nbsp;</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagenode~3f%29%29" class="RktValLink" data-pltdoc="x">pagenode?</a></span><span class="RktPn">)</span><span class="RktPn">)</span></p></blockquote></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktVar">p</span><span class="hspace">&nbsp;</span>:<span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace">&nbsp;</span><span class="RktVal">#f</span><span class="hspace">&nbsp;</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagenodeish~3f%29%29" class="RktValLink" data-pltdoc="x">pagenodeish?</a></span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktVar">pagetree</span><span class="hspace">&nbsp;</span>:<span class="hspace">&nbsp;</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagetree~3f%29%29" class="RktValLink" data-pltdoc="x">pagetree?</a></span><span class="hspace">&nbsp;</span>=<span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._current-pagetree%29%29" class="RktValLink" data-pltdoc="x">current-pagetree</a></span><span class="RktPn">)</span></td></tr></table></td></tr></table></blockquote></div><div class="SIntrapara">Return the pagenode immediately before <span class="RktVar">p</span>. For <span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._previous%2A%29%29" class="RktValLink" data-pltdoc="x">previous*</a></span>, return all the pagenodes before <span class="RktVar">p</span>, in sequence. In both cases, return <span class="RktVal">#f</span> if there aren&rsquo;t any pagenodes. The root pagenode is ignored.</div></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><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._current-pagetree%29%29" class="RktValLink" data-pltdoc="x">current-pagetree</a></span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">(</span><span class="RktVal">root</span><span class="hspace">&nbsp;</span><span class="RktVal">(</span><span class="RktVal">mama.html</span><span class="hspace">&nbsp;</span><span class="RktVal">son.html</span><span class="hspace">&nbsp;</span><span class="RktVal">daughter.html</span><span class="RktVal">)</span><span class="hspace">&nbsp;</span><span class="RktVal">uncle.html</span><span class="RktVal">)</span><span class="RktPn">)</span></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"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._previous%29%29" class="RktValLink" data-pltdoc="x">previous</a></span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">daughter.html</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">'son.html</span></p></td></tr><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._previous%29%29" class="RktValLink" data-pltdoc="x">previous</a></span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">son.html</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">'mama.html</span></p></td></tr><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._previous%29%29" class="RktValLink" data-pltdoc="x">previous</a></span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._previous%29%29" class="RktValLink" data-pltdoc="x">previous</a></span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">daughter.html</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">'mama.html</span></p></td></tr><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._previous%29%29" class="RktValLink" data-pltdoc="x">previous</a></span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">mama.html</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">#f</span></p></td></tr><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._previous%2A%29%29" class="RktValLink" data-pltdoc="x">previous*</a></span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">daughter.html</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">'(mama.html son.html)</span></p></td></tr><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._previous%2A%29%29" class="RktValLink" data-pltdoc="x">previous*</a></span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">uncle.html</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">'(mama.html son.html daughter.html)</span></p></td></tr></table></blockquote></td></tr></table></p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><table cellspacing="0" cellpadding="0" class="together"><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._pollen/pagetree..rkt)._next))"></a><span title="Provided from: pollen/pagetree | Package: pollen"><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._next%29%29" class="RktValDef RktValLink" data-pltdoc="x">next</a></span></span><span class="hspace">&nbsp;</span><span class="RktVar">p</span><span class="hspace">&nbsp;</span>[<span class="RktVar">pagetree</span>]<span class="RktPn">)</span><span class="hspace">&nbsp;</span>&rarr;<span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace">&nbsp;</span><span class="RktVal">#f</span><span class="hspace">&nbsp;</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagenode~3f%29%29" class="RktValLink" data-pltdoc="x">pagenode?</a></span><span class="RktPn">)</span></p></blockquote></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktVar">p</span><span class="hspace">&nbsp;</span>:<span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace">&nbsp;</span><span class="RktVal">#f</span><span class="hspace">&nbsp;</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagenodeish~3f%29%29" class="RktValLink" data-pltdoc="x">pagenodeish?</a></span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktVar">pagetree</span><span class="hspace">&nbsp;</span>:<span class="hspace">&nbsp;</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagetree~3f%29%29" class="RktValLink" data-pltdoc="x">pagetree?</a></span><span class="hspace">&nbsp;</span>=<span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._current-pagetree%29%29" class="RktValLink" data-pltdoc="x">current-pagetree</a></span><span class="RktPn">)</span></td></tr></table></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="together"><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._pollen/pagetree..rkt)._next*))"></a><span title="Provided from: pollen/pagetree | Package: pollen"><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._next%2A%29%29" class="RktValDef RktValLink" data-pltdoc="x">next*</a></span></span><span class="hspace">&nbsp;</span><span class="RktVar">p</span><span class="hspace">&nbsp;</span>[<span class="RktVar">pagetree</span>]<span class="RktPn">)</span><span class="hspace">&nbsp;</span>&rarr;<span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace">&nbsp;</span><span class="RktVal">#f</span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._listof%29%29" class="RktValLink" data-pltdoc="x">listof</a></span><span class="hspace">&nbsp;</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagenode~3f%29%29" class="RktValLink" data-pltdoc="x">pagenode?</a></span><span class="RktPn">)</span><span class="RktPn">)</span></p></blockquote></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktVar">p</span><span class="hspace">&nbsp;</span>:<span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace">&nbsp;</span><span class="RktVal">#f</span><span class="hspace">&nbsp;</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagenodeish~3f%29%29" class="RktValLink" data-pltdoc="x">pagenodeish?</a></span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktVar">pagetree</span><span class="hspace">&nbsp;</span>:<span class="hspace">&nbsp;</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagetree~3f%29%29" class="RktValLink" data-pltdoc="x">pagetree?</a></span><span class="hspace">&nbsp;</span>=<span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._current-pagetree%29%29" class="RktValLink" data-pltdoc="x">current-pagetree</a></span><span class="RktPn">)</span></td></tr></table></td></tr></table></blockquote></div><div class="SIntrapara">Return the pagenode immediately after <span class="RktVar">p</span>. For <span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._next%2A%29%29" class="RktValLink" data-pltdoc="x">next*</a></span>, return all the pagenodes after <span class="RktVar">p</span>, in sequence. In both cases, return <span class="RktVal">#f</span> if there aren&rsquo;t any pagenodes. The root pagenode is ignored.</div></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><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._current-pagetree%29%29" class="RktValLink" data-pltdoc="x">current-pagetree</a></span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">(</span><span class="RktVal">root</span><span class="hspace">&nbsp;</span><span class="RktVal">(</span><span class="RktVal">mama.html</span><span class="hspace">&nbsp;</span><span class="RktVal">son.html</span><span class="hspace">&nbsp;</span><span class="RktVal">daughter.html</span><span class="RktVal">)</span><span class="hspace">&nbsp;</span><span class="RktVal">uncle.html</span><span class="RktVal">)</span><span class="RktPn">)</span></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"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._next%29%29" class="RktValLink" data-pltdoc="x">next</a></span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">son.html</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">'daughter.html</span></p></td></tr><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._next%29%29" class="RktValLink" data-pltdoc="x">next</a></span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">daughter.html</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">'uncle.html</span></p></td></tr><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._next%29%29" class="RktValLink" data-pltdoc="x">next</a></span><span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._next%29%29" class="RktValLink" data-pltdoc="x">next</a></span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">son.html</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">'uncle.html</span></p></td></tr><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._next%29%29" class="RktValLink" data-pltdoc="x">next</a></span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">uncle.html</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">#f</span></p></td></tr><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._next%2A%29%29" class="RktValLink" data-pltdoc="x">next*</a></span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">mama.html</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">'(son.html daughter.html uncle.html)</span></p></td></tr><tr><td><span class="stt">&gt; </span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._next%2A%29%29" class="RktValLink" data-pltdoc="x">next*</a></span><span class="hspace">&nbsp;</span><span class="RktVal">'</span><span class="RktVal">daughter.html</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">'(uncle.html)</span></p></td></tr></table></blockquote></td></tr></table></p><h5>11.4.6.3<tt>&nbsp;</tt><a name="(part._.Utilities)"></a>Utilities</h5><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._pollen/pagetree..rkt)._pagetree-~3elist))"></a><span title="Provided from: pollen/pagetree | Package: pollen"><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagetree-~3elist%29%29" class="RktValDef RktValLink" data-pltdoc="x">pagetree-&gt;list</a></span></span><span class="hspace">&nbsp;</span><span class="RktVar">pagetree</span><span class="RktPn">)</span><span class="hspace">&nbsp;</span>&rarr;<span class="hspace">&nbsp;</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/pairs.html#%28def._%28%28quote._~23~25kernel%29._list~3f%29%29" class="RktValLink" data-pltdoc="x">list?</a></span></p></blockquote></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktVar">pagetree</span><span class="hspace">&nbsp;</span>:<span class="hspace">&nbsp;</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagetree~3f%29%29" class="RktValLink" data-pltdoc="x">pagetree?</a></span></td></tr></table></blockquote></div><div class="SIntrapara">Convert <span class="RktVar">pagetree</span> to a simple list. Equivalent to a pre-order depth-first traversal of <span class="RktVar">pagetree</span>.</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._((lib._pollen/pagetree..rkt)._in-pagetree~3f))"></a><span title="Provided from: pollen/pagetree | Package: pollen"><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._in-pagetree~3f%29%29" class="RktValDef RktValLink" data-pltdoc="x">in-pagetree?</a></span></span><span class="hspace">&nbsp;</span><span class="RktVar">pagenode</span><span class="hspace">&nbsp;</span>[<span class="RktVar">pagetree</span>]<span class="RktPn">)</span><span class="hspace">&nbsp;</span>&rarr;<span class="hspace">&nbsp;</span><span class="RktSym"><a href="http://docs.racket-lang.org/reference/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">&nbsp;&nbsp;</span><span class="RktVar">pagenode</span><span class="hspace">&nbsp;</span>:<span class="hspace">&nbsp;</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagenode~3f%29%29" class="RktValLink" data-pltdoc="x">pagenode?</a></span></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktVar">pagetree</span><span class="hspace">&nbsp;</span>:<span class="hspace">&nbsp;</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagetree~3f%29%29" class="RktValLink" data-pltdoc="x">pagetree?</a></span><span class="hspace">&nbsp;</span>=<span class="hspace">&nbsp;</span><span class="RktPn">(</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._current-pagetree%29%29" class="RktValLink" data-pltdoc="x">current-pagetree</a></span><span class="RktPn">)</span></td></tr></table></blockquote></div><div class="SIntrapara">Report whether <span class="RktVar">pagenode</span> is in <span class="RktVar">pagetree</span>.</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._((lib._pollen/pagetree..rkt)._path-~3epagenode))"></a><span title="Provided from: pollen/pagetree | Package: pollen"><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._path-~3epagenode%29%29" class="RktValDef RktValLink" data-pltdoc="x">path-&gt;pagenode</a></span></span><span class="hspace">&nbsp;</span><span class="RktVar">p</span><span class="RktPn">)</span><span class="hspace">&nbsp;</span>&rarr;<span class="hspace">&nbsp;</span><span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._pagenode~3f%29%29" class="RktValLink" data-pltdoc="x">pagenode?</a></span></p></blockquote></td></tr><tr><td><span class="hspace">&nbsp;&nbsp;</span><span class="RktVar">p</span><span class="hspace">&nbsp;</span>:<span class="hspace">&nbsp;</span><span class="RktSym"><a href="http://docs.racket-lang.org/sugar/index.html#%28def._%28%28lib._sugar%2Fcoerce..rkt%29._pathish~3f%29%29" class="RktValLink" data-pltdoc="x">pathish?</a></span></td></tr></table></blockquote></div><div class="SIntrapara">Convert path <span class="RktVar">p</span> to a pagenode &#8212;&#160;meaning, make it relative to <span class="RktSym">current-project-root</span>, run it through <span class="RktSym"><a href="file-types.html#%28def._%28%28lib._pollen%2Ffile..rkt%29._-~3eoutput-path%29%29" class="RktValLink" data-pltdoc="x"><span class="nobreak">-&gt;</span>output-path</a></span>, and convert it to a symbol. Does not tell you whether the resultant pagenode actually exists in the current pagetree (for that, use <span class="RktSym"><a href="Pagetree.html#%28def._%28%28lib._pollen%2Fpagetree..rkt%29._in-pagetree~3f%29%29" class="RktValLink" data-pltdoc="x">in-pagetree?</a></span>).</div></p><div class="navsetbottom"><span class="navleft"><div class="nosearchform"></div>&nbsp;&nbsp;</span><span class="navright">&nbsp;&nbsp;<a href="file-types.html" title="backward to &quot;11.3 File&quot;" data-pltdoc="x">&larr; prev</a>&nbsp;&nbsp;<a href="Module_reference.html" title="up to &quot;11 Module reference&quot;" data-pltdoc="x">up</a>&nbsp;&nbsp;<a href="Render.html" title="forward to &quot;11.5 Render&quot;" data-pltdoc="x">next &rarr;</a></span>&nbsp;</div></div></div><div id="contextindicator">&nbsp;</div></body></html>