stringr equivalent to grep
<p>Is there an <em>stringr</em> equivalent to base R's <code>grep</code> function?</p>

<p>I want to have the index of the string that matches. Example:</p>

<pre><code>grep("F|Y", LETTERS)
[1]  6 25
</code></pre>

<p>With <em>stringr</em> my workaround would be using <code>which</code> as follows:</p>

<pre><code>which(str_detect(LETTERS, "F|Y"))
[1]  6 25
</code></pre>