title: What is the meaning of %s+% in regex?
body: <p>I'm trying to understand the meaning of <code>%s+%</code> in this solution</p>
  <p><a href="https://stackoverflow.com/questions/26676045/replace-a-set-of-pattern-matches-with-corresponding-replacement-strings-in-r">Replace a set of pattern matches with corresponding replacement strings in R</a></p>
  <p>The important part of the code is this</p>
  <pre><code>xxx_replace_xxx_pcre(string, &quot;\\b&quot; %s+% patterns %s+% &quot;\\b&quot;, replacements)
  </code></pre>
  <p>I know that <code>\s+</code> is used to match one or more spaces, but what is the meaning inside <code>%%</code> ?</p>
  <p>I tried to use the code without it, because I just want to match inside word boundaries, but it gives an error</p>
  <pre><code>xxx_replace_xxx_pcre(string, &quot;\\b&quot; patterns &quot;\\b&quot;, replacements)
  </code></pre>
  <p>I already researched about special PCRE symbols and other things, but didn't find anything. Can anyone give me some explanation about it?</p>