line"><span style="--shiki-dark:#6A737D;--shiki-light:#6A737D;"> * 该动作的上一步方法</span></span>
<span class="line"><span style="--shiki-dark:#6A737D;--shiki-light:#6A737D;"> */</span></span>
<span class="line"><span style="--shiki-dark:#B392F0;--shiki-light:#6F42C1;">prev</span><span style="--shiki-dark:#E1E4E8;--shiki-light:#24292E;">(): </span><span style="--shiki-dark:#F97583;--shiki-light:#D73A49;">void</span></span></code></pre></div></div></div></main><footer class="VPDocFooter" data-v-cd