968 lines
24 KiB
HTML
968 lines
24 KiB
HTML
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
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"http://www.w3.org/TR/html4/loose.dtd"><!-- DO NOT EDIT THIS FILE-->
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<!-- Edit the .tex version instead-->
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<html>
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<head>
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<title>Introduction to stex</title>
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<link href="stex.css" rel="stylesheet" type="text/css">
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</head>
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<body>
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<h1>Introduction to stex</h1>
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<h2>R. Kent Dybvig and Oscar Waddell</h2>
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<h3>April 2016</h3>
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<p>
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<table cellpadding=0 cellspacing=0>
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<tr><td align="right"><b>1. </b><td><b><a class=plain href="./stex.html#g0">Overview</a></b></td></tr>
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<tr><td align="right"><b>2. </b><td><b><a class=plain href="./stex.html#g1">Installation</a></b></td></tr>
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<tr><td align="right"><b>3. </b><td><b><a class=plain href="./stex.html#g2">Usage notes</a></b></td></tr>
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<tr><td align="right"><b>4. </b><td><b><a class=plain href="./stex.html#g3">Basic stex commands</a></b></td></tr>
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<tr><td></td><td><table cellpadding=0 cellspacing=0>
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<tr><td><b>4.1. </b></td><td><b><a class=plain href="./stex.html#g4">Inline code</a></b></td></tr>
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<tr><td><b>4.2. </b></td><td><b><a class=plain href="./stex.html#g5">Code displays</a></b></td></tr>
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<tr><td><b>4.3. </b></td><td><b><a class=plain href="./stex.html#g6">Variables</a></b></td></tr>
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<tr><td><b>4.4. </b></td><td><b><a class=plain href="./stex.html#g7">Raw text in code</a></b></td></tr>
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<tr><td><b>4.5. </b></td><td><b><a class=plain href="./stex.html#g8">Generated output</a></b></td></tr>
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<tr><td><b>4.6. </b></td><td><b><a class=plain href="./stex.html#g9">Verbatim Scheme displays</a></b></td></tr>
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</table></td></tr>
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<tr><td align="right"><b>5. </b><td><b><a class=plain href="./stex.html#g10">Scheme transcripts</a></b></td></tr>
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<tr><td></td><td><table cellpadding=0 cellspacing=0>
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<tr><td><b>5.1. </b></td><td><b><a class=plain href="./stex.html#g11">Automatic transcript generation</a></b></td></tr>
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<tr><td><b>5.2. </b></td><td><b><a class=plain href="./stex.html#g12">Loading initialization code</a></b></td></tr>
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</table></td></tr>
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<tr><td align="right"><b>6. </b><td><b><a class=plain href="./stex.html#g13">html-prep support for the <tt>tabular</tt> environment</a></b></td></tr>
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</table>
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<p>
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<p>
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<a name="g0"></a>
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<h3><a name="./stex:h0"></a>1. Overview</h3>
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<p>
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The <i>stex</i> package consists of two main programs and some supporting
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items, such as make files, make-file templates, class files, and style
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files.
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The two main programs are <b>scheme-prep</b> and <b>html-prep</b>.
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<b>scheme-prep</b> performs a conversion from "stex"-formatted files
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into latex-formatted files, while <b>html-prep</b> converts (some)
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latex-formatted files into html-formatted files.
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<p>
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An stex file is really just a latex file extended with a handful of
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commands for including Scheme code (or pretty much any other kind of code,
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as long as you don't plan to use the Scheme-specific transcript support)
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in a document, plus a couple of additional features rather arbitrarily
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thrown in.
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<p>
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The subset of latex-formatted files <b>html-prep</b> is capable of
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handling is rather small but has nevertheless been useful for our
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purposes, which include producing html versions of a couple of books
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(<i>The Scheme Programming Language</i>, Editions 2-4 and the Chez Scheme
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User's Guides for Versions 6-9), the scheme.com web site, class websites,
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class assignments, and various other documents.
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<p>
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<a name="g1"></a>
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<h3><a name="./stex:h1"></a>2. Installation</h3>
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<p>
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A prerequisite to building and using stex is to have Chez Scheme or
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Petite Chez Scheme installed on your system.
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You'll also need pdflatex, dvips, ghostscript, and netbpm.
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We've run stex under Linux and OS X but have not tried to run it under
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Windows.
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<p>
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The simplest way to install stex for your personal use is to clone the
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stex directory into your home directory, cd into the stex directory,
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and run make:
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<p>
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<p><tt>make BIN=<i>bindir</i></tt>
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<p>where <tt><i>bindir</i></tt> is the directory where make will find the scheme or
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petite executables.
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<p>
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This will create a subdirectory, named for the installed Chez Scheme
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machine type, containing binary versions of the programs.
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<p>
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You can also use "make install" to make stex available for other users.
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<p>
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<p><tt>sudo make install BIN=<i>bindir</i> LIB=<i>libdir</i></tt>
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<p>where <tt><i>bindir</i></tt> is as described above, and <tt><i>libdir</i></tt> is the
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directory where the stex library directory should be installed.
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<p>
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<a name="g2"></a>
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<h3><a name="./stex:h2"></a>3. Usage notes</h3>
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<p>
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The simplest way to get started with stex is to get this document to
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build (in the doc directory) and create your own document by cloning
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this document's source file (stex.stex) and make file (Makefile).
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If you've installed stex in your home directory, you should be able to
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build this document by running "make" without arguments in the doc
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directory.
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If you've installed stex elsewhere, you'll first have to modify the
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include for Mf-stex to reflect its installed location.
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<p>
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Makefile is where you declare your stex sources and various other things,
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like bibtex and graphics files.
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If you don't have anything much more complicated than this document,
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you might just need to change the line that declares the main stex entry
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point, i.e., the line that reads <tt>x = stex</tt>, to reflect the name
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of your document.
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<p>
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The make is orchestrated by Mf-stex, which knows how to run
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<b>scheme-prep</b>, <b>html-prep</b>, <b>pdflatex</b> (multiple
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times), and various other commands to produce both pdf and html versions
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of the stex document.
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<p>
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You can also consult the more elaborate stex source and make files for the
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Chez Scheme User's Guide in the csug directory of a Chez Scheme release.
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<p>
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<a name="g3"></a>
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<h3><a name="./stex:h3"></a>4. Basic stex commands</h3>
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<p>
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<a name="g4"></a>
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<h4><a name="./stex:h4"></a>4.1. Inline code</h4>
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<p>
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An stex document includes inline Scheme (or other) code via the
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<tt>\scheme</tt> command, e.g.:
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<p>
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<blockquote>
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<pre>
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When called with two arguments, \scheme{cons} creates a pair of the two
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arguments, e.g., \scheme{(cons 3 4)} produces \scheme{(3 . 4)}.
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</pre>
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<p>
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</blockquote>
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<p>
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produces:
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<p>
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<blockquote>
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When called with two arguments, <tt>cons</tt> creates a pair of the two
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arguments, e.g., <tt>(cons 3 4)</tt> produces <tt>(3 . 4)</tt>.
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</blockquote>
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<p>
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<a name="g5"></a>
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<h4><a name="./stex:h5"></a>4.2. Code displays</h4>
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<p>
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An stex document includes out-of-line Scheme (or other) code via
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<tt>\schemedisplay</tt> and <tt>\endschemedisplay</tt>, e.g.:
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<p>
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<blockquote>
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<pre>
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\schemedisplay
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(define fact
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(lambda (x)
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"a light year is a measure of distance"))
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(define fib
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(lambda (x)
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"a light year is a measure of time"))
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\endschemedisplay
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</pre>
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<p>
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</blockquote>
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<p>
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produces:
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<p>
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<blockquote>
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<p><tt>(define fact<br>
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(lambda (x)<br>
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"a light year is a measure of distance"))
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<br>
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<br>
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(define fib<br>
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(lambda (x)<br>
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"a light year is a measure of time"))</tt>
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<p></blockquote>
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<p>
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Within a Scheme display, <tt>;=></tt> is converted into a double right arrow
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(<img src="math/stex/0.gif" alt="<graphic>">), <tt>;-></tt> into a single right arrow (<img src="math/stex/1.gif" alt="<graphic>">), and
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<tt>;==</tt> into a phantom of the same size.
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This is useful for showing what a piece of code translates or evaluates to,
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e.g.:
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<p>
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<blockquote>
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<pre>
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A \scheme{let} expression expands into a call to a \scheme{lambda}
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expression, e.g.:
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\schemedisplay
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(let ([a 17]) ;-> ((lambda (a) (+ a a))
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(+ a a)) ;== 17)
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\endschemedisplay
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A \scheme{let} expression first evaluates the right-hand-side
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expression, then evaluates the body in an environment that binds
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the left-hand-side variable to the resulting value, e.g.:
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\schemedisplay
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(let ([a 17]) ;=> 17
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(+ a a))
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\endschemedisplay
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</pre>
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<p>
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</blockquote>
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<p>
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produces
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<p>
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<blockquote>
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A <tt>let</tt> expression expands into a call to a <tt>lambda</tt>
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expression, e.g.:
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<p><tt>(let ([a 17]) <img src="math/stex/1.gif" alt="<graphic>"> ((lambda (a) (+ a a))<br>
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(+ a a)) <img src="gifs/ghostRightarrow.gif"> 17)</tt>
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<p>A <tt>let</tt> expression first evaluates the right-hand-side
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expression, then evaluates the body in an environment that binds
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the left-hand-side variable to the resulting value, e.g.:
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<p><tt>(let ([a 17]) <img src="math/stex/0.gif" alt="<graphic>"> 17<br>
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(+ a a))</tt>
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<p></blockquote>
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<p>
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<a name="g6"></a>
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<h4><a name="./stex:h6"></a>4.3. Variables</h4>
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<p>
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Code can include emphasized variables via the <tt>\var</tt> command, e.g.:
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<p>
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<blockquote>
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<pre>
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\scheme{(let ([\var{x} \var{e}]) \var{body})} binds the variable \var{x} to
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the value of \var{e} in \var{body}.
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</pre>
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<p>
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</blockquote>
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<p>
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produces:
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<p>
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<blockquote>
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<tt>(let ([<i>x</i> <i>e</i>]) <i>body</i>)</tt> binds the variable <tt><i>x</i></tt> to
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the value of <tt><i>e</i></tt> in <tt><i>body</i></tt>.
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</blockquote>
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<p>
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If the text within a <tt>\var</tt> form contains an underscore, the
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following character or bracketed subform is converted into a subscript,
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e.g., <tt>\var{abc_3}</tt>
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produces <tt><i>abc<sub>3</sub></i></tt>, and <tt>\var{7e5_16}</tt>
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produces <tt><i>7e5<sub>16</sub></i></tt>.
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<p>
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<tt>\var</tt> forms may appear within a <tt>\scheme</tt> form, within a Scheme display
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formed by <tt>\schemedisplay</tt> and <tt>\endschemedisplay</tt> commands,
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or by itself outside of either.
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<p>
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<a name="g7"></a>
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<h4><a name="./stex:h7"></a>4.4. Raw text in code</h4>
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<p>
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Raw text can be included in code via the <tt>\raw</tt> command.
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For example:
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<p>
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<blockquote>
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<pre>
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\schemedisplay
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(sqrt \raw{$x$}) \is \raw{$\sqrt{x}$}.
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\endschemedisplay
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</pre>
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<p>
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</blockquote>
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<p>
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produces:
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<p>
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<blockquote>
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<p><tt>(sqrt <i>x</i>) <img src="math/stex/0.gif" alt="<graphic>"> <img src="math/stex/2.gif" alt="<graphic>">.</tt>
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<p></blockquote>
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<p>
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<a name="g8"></a>
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<h4><a name="./stex:h8"></a>4.5. Generated output</h4>
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<p>
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Output generated by a Scheme program can be inserted into the output via
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<tt>\generated</tt> and <tt>\endgenerated</tt> commands, e.g.:
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<p>
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<blockquote>
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<pre>
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\generated
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(let ()
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(define fibs
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(lambda (x y n)
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(if (= n 0)
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'()
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(cons x (fibs y (+ x y) (- n 1))))))
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(let ([n 5])
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(printf "first ~r primes: ~{~s~^, ~}\n" n (fibs 0 1 n))))
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\endgenerated
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</pre>
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<p>
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</blockquote>
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<p>
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produces:
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<p>
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<blockquote>
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first five primes: 0, 1, 1, 2, 3
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<p>
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</blockquote>
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<p>
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<a name="g9"></a>
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<h4><a name="./stex:h9"></a>4.6. Verbatim Scheme displays</h4>
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<p>
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When special features, like <tt>\var</tt> forms, need to be
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suppressed within a Scheme display, a document can use
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<tt>\schemeverbatim</tt> and <tt>\endschemeverbatim</tt> instead of
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<tt>\schemedisplay</tt> and <tt>\endschemedisplay</tt>.
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This document makes extensive use of this feature.
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<p>
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<a name="g10"></a>
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<h3><a name="./stex:h10"></a>5. Scheme transcripts</h3>
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<p>
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<a name="g11"></a>
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<h4><a name="./stex:h11"></a>5.1. Automatic transcript generation</h4>
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<p>
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The <b>scheme-prep</b> package supports a
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<tt>\transcript</tt> command for automatically generating Scheme transcripts
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from input supplied in the document source.
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All text from the <tt>\transcript</tt> marker up to and including the
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<tt>\endtranscript</tt> marker is replaced with a transcript generated
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by supplying the intervening text as the input to a Scheme café (REPL).
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If the Scheme transcript needs to contain the sequence
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<tt>\endtranscript</tt>, a different terminator may be specified as an
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optional argument to <tt>\transcript</tt>.
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The terminator must be a backslash followed by one or more alphabetic
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characters, and is specified without the backslash in the optional argument.
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<p>
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Three pairs of commands may be redefined to customize the typesetting
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of different elements within generated transcripts.
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To modify the typesetting of error messages, redefine <tt>\transerr</tt>
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and <tt>\endtranserr</tt>.
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To modify the typesetting of user input read from the current input port
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of the café, redefine <tt>\transin</tt> and <tt>\endtransin</tt>.
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To modify the typesetting of program output written to the current
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output port of new café, redefine <tt>\transout</tt> and
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<tt>\endtransout</tt>.
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<p>
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For example, the following:
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<p>
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<blockquote>
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<pre>
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\transcript
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(define f
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(lambda (x) ; indentation and comments are
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(if (zero? x) ; preserved in the transcript
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1
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(* x (f (- x 1))))))
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(values f (f 0) (f 5) (f 20))
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(trace f)
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(f 4)
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\endtranscript
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</pre>
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<p>
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</blockquote>
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<p>
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produces:
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<p>
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<blockquote>
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<p><tt>> (define f<br>
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(lambda (x) ; indentation and comments are<br>
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(if (zero? x) ; preserved in the transcript<br>
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1<br>
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(* x (f (- x 1))))))<br>
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> (values f (f 0) (f 5) (f 20))<br>
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#<procedure f><br>
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1<br>
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120<br>
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2432902008176640000<br>
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> (trace f)<br>
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(f)<br>
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> (f 4)<br>
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<font color="#0000ff">|(f 4)<br>
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| (f 3)<br>
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| |(f 2)<br>
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| | (f 1)<br>
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| | |(f 0)<br>
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| | |1<br>
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| | 1<br>
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| |2<br>
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| 6<br>
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|24<br>
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</font>24</tt>
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<p></blockquote>
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<p>
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The following example shows how to specify a different transcript
|
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terminator and shows the default formatting imposed by <tt>\transerr</tt>,
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<tt>\transin</tt>, and <tt>\transout</tt>.
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<p>
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<blockquote>
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<pre>
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\transcript[\stopthistranscript]
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#e4.5
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(begin (display "Enter a character: ") (read-char))
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(begin (display "Enter a character: ") (read-char))Z
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(begin (clear-input-port) (display "Enter a character: ") (read-char))
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Z
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(list (read-char) (read-char) (read-char))abc def
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(define silly-repl
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(lambda (prompt)
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(display prompt)
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(let ([x (read)])
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(unless (eof-object? x)
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(let ([result (eval x)])
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(unless (eq? result (void))
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(pretty-print result))
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(silly-repl prompt))))))
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(silly-repl "Enter a Scheme expression: ")
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(list 1
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2
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3)
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(silly-repl "Now what? ")
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(define interview
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(lambda ()
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(let* ([fname (begin (display "First name: ") (read))]
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[lname (begin (display "Last name: ") (read))])
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(printf "Hello ~a ~a!~%" fname lname))))
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(interview)
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john
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doe
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#!eof
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(printf "good to be back~%")
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#!eof
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\stopthistranscript
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</pre>
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<p>
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</blockquote>
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<p>
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produces:
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<p>
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<blockquote>
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<p><tt>> #e4.5<br>
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9/2<br>
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> (begin (display "Enter a character: ") (read-char))<font color="#ff0000"><br>
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</font><font color="#0000ff">Enter a character: </font>#\newline<br>
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> (begin (display "Enter a character: ") (read-char))<font color="#ff0000">Z</font><br>
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<font color="#0000ff">Enter a character: </font>#\Z<br>
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> (begin (clear-input-port) (display "Enter a character: ") (read-char))<br>
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|
<font color="#0000ff">Enter a character: </font><font color="#ff0000">Z</font><br>
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#\Z<br>
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> (list (read-char) (read-char) (read-char))<font color="#ff0000">abc</font> def<br>
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|
(#\b #\c #\a)<br>
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> <br>
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|
|
Exception: variable def is not bound<br>
|
|
|
|
Type (debug) to enter the debugger.<br>
|
|
|
|
> (define silly-repl<br>
|
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|
|
(lambda (prompt)<br>
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|
|
(display prompt)<br>
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|
|
(let ([x (read)])<br>
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|
|
(unless (eof-object? x)<br>
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|
(let ([result (eval x)])<br>
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|
|
(unless (eq? result (void))<br>
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|
|
(pretty-print result))<br>
|
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|
|
(silly-repl prompt))))))<br>
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|
|
> (silly-repl "Enter a Scheme expression: ")<font color="#ff0000"><br>
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|
</font><font color="#0000ff">Enter a Scheme expression: </font><font color="#ff0000">(list 1<br>
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|
</font> <font color="#ff0000"> 2<br>
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|
|
</font> <font color="#ff0000"> 3)<br>
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|
|
</font><font color="#0000ff">(1 2 3)<br>
|
|
|
|
Enter a Scheme expression: </font><font color="#ff0000">(silly-repl "Now what? ")<br>
|
|
|
|
</font><font color="#0000ff">Now what? </font><font color="#ff0000">(define interview<br>
|
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|
|
</font> <font color="#ff0000"> (lambda ()<br>
|
|
|
|
</font> <font color="#ff0000"> (let* ([fname (begin (display "First name: ") (read))]<br>
|
|
|
|
</font> <font color="#ff0000"> [lname (begin (display "Last name: ") (read))])<br>
|
|
|
|
</font> <font color="#ff0000"> (printf "Hello ~a ~a!~%" fname lname))))<br>
|
|
|
|
</font><font color="#0000ff">Now what? </font><font color="#ff0000">(interview)<br>
|
|
|
|
</font><font color="#0000ff">First name: </font><font color="#ff0000">john<br>
|
|
|
|
</font><font color="#0000ff">Last name: </font><font color="#ff0000"> doe<br>
|
|
|
|
</font><font color="#0000ff">Hello john doe!<br>
|
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|
|
Now what? </font><font color="#ff0000">#!eof<br>
|
|
|
|
</font><font color="#0000ff">Enter a Scheme expression: </font><font color="#ff0000">(printf "good to be back~%")<br>
|
|
|
|
</font><font color="#0000ff">good to be back<br>
|
|
|
|
Enter a Scheme expression: </font><font color="#ff0000">#!eof</font></tt>
|
|
<p></blockquote>
|
|
|
|
<p>
|
|
Transcripts do not include a trailing prompt by design.
|
|
This is done in such a way that an explicitly displayed string that
|
|
happens to look like the prompt is not suppressed.
|
|
For example:
|
|
|
|
<p>
|
|
<blockquote>
|
|
<pre>
|
|
\transcript
|
|
(begin (display "> \n") (exit))
|
|
\endtranscript
|
|
</pre>
|
|
|
|
|
|
<p>
|
|
</blockquote>
|
|
|
|
<p>
|
|
should leave the apparent prompt alone since it is generated as program
|
|
output.
|
|
|
|
<p>
|
|
<blockquote>
|
|
|
|
<p><tt>> (begin (display "> \n") (exit))<br>
|
|
|
|
<font color="#0000ff">> <br>
|
|
|
|
</font></tt>
|
|
<p></blockquote>
|
|
|
|
<p>
|
|
Prompt suppression works even with
|
|
changes to <tt>waiter-prompt-string</tt>.
|
|
For example:
|
|
|
|
<p>
|
|
<blockquote>
|
|
<pre>
|
|
\transcript
|
|
(waiter-prompt-string "antelope? ")
|
|
"no thanks"
|
|
\endtranscript
|
|
</pre>
|
|
|
|
|
|
<p>
|
|
</blockquote>
|
|
|
|
<p>
|
|
produces no trailing "antelope? " prompt:
|
|
|
|
<p>
|
|
<blockquote>
|
|
|
|
<p><tt>> (waiter-prompt-string "antelope? ")<br>
|
|
|
|
antelope? "no thanks"<br>
|
|
|
|
"no thanks"</tt>
|
|
<p></blockquote>
|
|
|
|
<p>
|
|
|
|
<a name="g12"></a>
|
|
|
|
|
|
<h4><a name="./stex:h12"></a>5.2. Loading initialization code</h4>
|
|
|
|
|
|
|
|
|
|
<p>
|
|
The <tt>stex</tt> commands <tt>\schemeinit</tt> and <tt>\endschemeinit</tt>
|
|
are used to bracket Scheme expressions that should be evaluated without
|
|
generating a transcript of the results.
|
|
This is useful, for example, when writing the description of a programming
|
|
assignment. The solutions can be loaded via <tt>\schemeinit</tt> and a
|
|
transcript showing how the solutions behave can be generated using the
|
|
<tt>\transcript</tt> command.
|
|
|
|
<p>
|
|
For example, the following text:
|
|
|
|
<p>
|
|
<blockquote>
|
|
<pre>
|
|
\schemeinit
|
|
(waiter-prompt-string ">") ; restore the original prompt setting so we
|
|
; don't get "antelope?" as the prompt
|
|
(define compute-length
|
|
(lambda (x)
|
|
(cond
|
|
[(list? x) (length x)]
|
|
[(vector? x) (vector-length x)]
|
|
[(string? x) (string-length x)]
|
|
[else (errorf 'compute-length "cannot handle ~s" ls)])))
|
|
\endschemeinit
|
|
\emph{The \scheme{compute-length} procedure behaves as follows:}
|
|
\transcript
|
|
(compute-length '())
|
|
(compute-length '(a b c))
|
|
(compute-length "abcd")
|
|
(compute-length (vector 1 2 3 4 5 6))
|
|
(compute-length compute-length)
|
|
\endtranscript
|
|
</pre>
|
|
|
|
|
|
<p>
|
|
</blockquote>
|
|
|
|
<p>
|
|
produces the output shown below.
|
|
|
|
<p>
|
|
<blockquote>
|
|
|
|
<p>
|
|
<i>The <tt>compute-length</tt> procedure behaves as follows:</i>
|
|
|
|
<p><tt>> (compute-length '())<br>
|
|
|
|
0<br>
|
|
|
|
> (compute-length '(a b c))<br>
|
|
|
|
3<br>
|
|
|
|
> (compute-length "abcd")<br>
|
|
|
|
4<br>
|
|
|
|
> (compute-length (vector 1 2 3 4 5 6))<br>
|
|
|
|
6<br>
|
|
|
|
> (compute-length compute-length)
|
|
<br>
|
|
<br>
|
|
Exception in compute-length: cannot handle #<procedure compute-length><br>
|
|
|
|
Type (debug) to enter the debugger.</tt>
|
|
<p></blockquote>
|
|
|
|
<p>
|
|
the last line of input intentionally causes an error, which is
|
|
displayed just as it would be displayed in a café.
|
|
|
|
<p>
|
|
|
|
<a name="g13"></a>
|
|
|
|
|
|
<h3><a name="./stex:h13"></a>6. html-prep support for the <tt>tabular</tt> environment</h3>
|
|
|
|
|
|
|
|
|
|
<p>
|
|
Support for tables comes with a few caveats:
|
|
|
|
<p>
|
|
<ol>
|
|
<a name="g14"></a><li><tt>@{}</tt> directives within <tt>tabular</tt>
|
|
column specifiers are flat-out ignored for the time being.
|
|
<a name="g15"></a><li><tt>|</tt> directives within <tt>tabular</tt>
|
|
column specifiers are essentially ignored. Their only effect is
|
|
to globally enable borders for the entire HTML table.
|
|
<a name="g16"></a><li><tt>\hrule</tt> and <tt>\cline</tt> are not yet implemented.
|
|
<a name="g17"></a><li>no warranty is expressed or implied.
|
|
</ol>
|
|
<p>
|
|
|
|
<p>
|
|
The following code:
|
|
|
|
<p>
|
|
<blockquote>
|
|
<pre>
|
|
\begin{tabular}{rcl|r}
|
|
y &=& f(x) & without loss of generality \\
|
|
z & \multicolumn{2}{r}{whee} & this is fun? \\
|
|
\multicolumn{4}{c}{
|
|
\begin{tabular}{cc}
|
|
1 & 2 \\
|
|
3 & 4
|
|
\end{tabular}
|
|
} \\
|
|
a & b & c & d \\
|
|
12345 & z & \multicolumn{2}{l}{\scheme{(define~x~"foo")}}
|
|
\end{tabular}
|
|
</pre>
|
|
|
|
</blockquote>
|
|
|
|
<p>
|
|
generates this table:
|
|
|
|
<p>
|
|
<blockquote>
|
|
<TABLE border="1"><TR><TD nowrap align="right">
|
|
y </TD><TD nowrap align="center">=</TD><TD nowrap align="left"> f(x) </TD><TD nowrap align="right"> without loss of generality </TD></TR><TR><TD nowrap align="right">
|
|
z </TD><TD nowrap colspan="2" align="right"> whee </TD><TD nowrap align="left"> this is fun? </TD></TR><TR><TD nowrap colspan="4" align="center">
|
|
|
|
<TABLE><TR><TD nowrap align="center">
|
|
1 </TD><TD nowrap align="center"> 2 </TD></TR><TR><TD nowrap align="center">
|
|
3 </TD><TD nowrap align="center"> 4
|
|
</TD></TR></TABLE>
|
|
</TD></TR><TR><TD nowrap align="right">
|
|
a </TD><TD nowrap align="center"> b </TD><TD nowrap align="left"> c </TD><TD nowrap align="right"> d </TD></TR><TR><TD nowrap align="right">
|
|
12345 </TD><TD nowrap align="center"> z </TD><TD nowrap colspan="2" align="left"> <tt>(define x "foo")</tt>
|
|
</TD></TR></TABLE>
|
|
</blockquote>
|
|
|
|
<p>
|
|
|
|
|
|
© 1998-2016 R. Kent Dybvig and Oscar Waddell</body>
|
|
</html>
|