This article explains how expressions are evaluated in XC=BASIC.
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<polygon points="17 149 9 145 9 153"/><a xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="#Simplexp" xlink:title="Simplexp">
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<text class="nonterminal" x="59" y="153">Simplexp</text></a><rect x="51" y="91" width="30" height="32" rx="10"/>
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<text class="terminal" x="59" y="109">&</text>
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<text class="terminal" x="59" y="65">|</text>
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<text class="terminal" x="59" y="21">^</text>
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