 update or modify. But perhaps more importantly is that it’s not particularly <em>literate</em>: the code merely ‘happens’ to give the right answer, rather than expressing the method too.</p>
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<div id="income-tax-calculations-are-rolling-joins" class="section level2">
<h2 class="hasAnchor">
<a href="#income-tax-calculations-are-rolling-joins" class="anchor"></a>Income tax calculations are rolling joins</h2>
<p>A more natural and expressive approach is to treat the income tax as a rolling join.</