nown as <a href="dart-ui/FontWeight/w400-constant.html">w400</a>).</p>
<p>The <code>t</code> argument represents position on the timeline, with 0.0 meaning
that the interpolation has not started, returning <code>a</code> (or something
equivalent to <code>a</code>), 1.0 meaning that the interpolation has finished,
returning <code>b</code> (or something equivalent to <code>b</code>), and values in between
meaning that the interpolation is at the relevant point on the timeline
between <code>a</code> and <code>