expression would already have been “thunk” about. <a class="citation" href="https://mitp-content-server.mit.edu/books/content/sectbyfn/books_pres_0/6515/sicp.zip/full-text/book/book-Z-H-27.html#footnote_Temp_580" title="SICP Chapter 4, Footnote 34">(Footnote&nbsp;4.34)</a></p>
</blockquote>
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<h3 id="4.2.2.1" class="anchor">
<a class="anchor__link link" href="#4.2.2.1" aria-hidden="true">#</a> Modifying the evaluator
</h3>
<ul>
<li>The main change required is the procedure application logic in <cod