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<title>Teachpack : Documents</title>
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<a href="index.html">Teachpacks for How to Design Programs</a>
<h1>Documents</h1>
<hr> <h3><a name="docs.ss">docs.ss</a></h3> <!-- DOCNOTE="teach=docs.ss" -->
The teachpack <code>docs.ss</code> provides three operations:
<menu>
<li> <code><a name="atom?">atom?</a> : SchemeValue -> bool</code>
<br> which determines whether or not a
Scheme value is a number, a symbol, or a string; <br>
Note: This notion of atom is different from that in the compat.ss library.
<li> <code><a name="annotation?">annotation?</a> : SchemeValue -> bool</code>
<br> which determines whether or not a
Scheme symbol is a document annotation;
<li> <code><a name="end-annotation">end-annotation</a> : annotation -> annotation</code>
<br>which consumes an annotation and
produces a matching ending; and
<li> <code> <a name="write-file">write-file</a> : (list-of atom) [string]-> void <code>
<br> which consumes a list of annotated symbols
and prints them out as a "file"; it returns nothing.
if the string argument is present, it is interpreted as a file name:
the words are written to this file; if the file exists, it is deleted
</menu>
<p>Sample session: set teachpack to <code>docs.ss</code> and execute:
<pre>
> (annotation? 0)
#f
> (annotation? '<bold>)
#t
> (end-annotation 0)
end-annotation: not an annotation: 0
> (write-file (list 'a 'b))
a b
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