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<span id="Notes-about-Backquote"></span><div class="header">
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Previous: <a href="Backquote.html" accesskey="p" rel="prev">Backquote</a>, Up: <a href="Backquote.html" accesskey="u" rel="up">Backquote</a> </p>
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<hr>
<span id="Notes-about-Backquote-1"></span><h4 class="subsubsection">2.4.6.1 Notes about Backquote</h4>
<p>Since the exact manner in which the <i>Lisp reader</i> will parse
an <i>expression</i> involving the <i>backquote</i> <i>reader macro</i>
is not specified, an <i>implementation</i> is free to choose any
representation that preserves the semantics described.
</p>
<p>Often an <i>implementation</i> will choose a representation that facilitates
pretty printing of the expression, so that <tt>(pprint `(a ,b))</tt> will display
<tt>`(a ,b)</tt> and not, for example, <tt>(list 'a b)</tt>. However, this is not a
requirement.
</p>
<p>Implementors who have no particular reason to make one choice or another
might wish to refer to <b>IEEE Standard for the Scheme Programming Language</b>, which identifies a popular choice of
representation for such expressions that might provide useful to be useful
compatibility for some user communities. There is no requirement, however,
that any <i>conforming implementation</i> use this particular representation.
This information is provided merely for cross-reference purposes.
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