Extract string before "|"
<p>I have a data set wherein a column looks like this:</p>

<pre><code>ABC|DEF|GHI,  
ABCD|EFG|HIJK,  
ABCDE|FGHI|JKL,  
DEF|GHIJ|KLM,  
GHI|JKLM|NO|PQRS,  
BCDE|FGHI|JKL  
</code></pre>

<p>.... and so on  </p>

<p>I need to extract the characters that appear before the first <code>|</code> symbol.  </p>

<p>In Excel, we would use a combination of MID-SEARCH or a LEFT-SEARCH, R contains <code>substr()</code>.</p>

<p>The syntax is - <code>substr(x, &lt;start&gt;,&lt;stop&gt;)</code>  </p>

<p>In my case, start will always be 1. For stop, we need to search by <code>|</code>. How can we achieve this? Are there alternate ways to do this?</p>