擅长:python、mysql、java
<p>使用<a href="https://pypi.org/project/regex/" rel="nofollow noreferrer">regex</a>模块(在注释中由<a href="https://stackoverflow.com/users/3832970/wiktor-stribi%c5%bcew">Wiktor Stribiżew</a>回答)</p>
<pre><code>>>> import regex
>>> line = 'spam'
>>> regex.sub(r'\G\s', '&nbsp;', line)
'spam'
>>> line = ' eggs'
>>> regex.sub(r'\G\s', '&nbsp;', line)
'&nbsp;eggs'
>>> line = ' spam eggs'
>>> regex.sub(r'\G\s', '&nbsp;', line)
'&nbsp;&nbsp;spam eggs'
</code></pre>
<p>根据文档:</p>
<blockquote>
<p>\G</p>
<p>A search anchor has been added. It matches at the position where each
search started/continued and can be used for contiguous matches or in
negative variable-length lookbehinds to limit how far back the
lookbehind goes</p>
</blockquote>