<p>In <a href="https://github.com/mlpack/mlpack/pull/694#discussion_r69402370">src/mlpack/core/data/dataset_info.hpp</a>:</p>
<pre style='color:#555'>&gt; @@ -101,8 +107,12 @@ class DatasetMapper
&gt;      ar &amp; data::CreateNVP(maps, &quot;maps&quot;);
&gt;    }
&gt;  
&gt; +  //! Return the policy of the mapper.
&gt;    PolicyType&amp; Policy() const;
</pre>
<p>I think the return type should be PolicyType const&amp;, else the compiler could not compile(this make sense, const member function return reference non-const data member is weird).</p>

<p style="font-size:small;-webkit-text-size-adjust:none;color:#666;">&mdash;<br />You are receiving this because you are subscribed to this thread.<br />Reply to this email directly, <a href="https://github.com/mlpack/mlpack/pull/694/files/21d94c04652e8faadd5e8991103a3b73b4c81033..a92afaaafb1af3deede31c1a5ef0b508bfbfe105#r69402370">view it on GitHub</a>, or <a href="https://github.com/notifications/unsubscribe/AJ4bFByOHOIL69cPPqFNeogFJCca-GSmks5qSGvWgaJpZM4I07W-">mute the thread</a>.<img alt="" height="1" src="https://github.com/notifications/beacon/AJ4bFC6vrsEOl8hZ2IDlVB5Ss23g3dmeks5qSGvWgaJpZM4I07W-.gif" width="1" /></p>
<div itemscope itemtype="http://schema.org/EmailMessage">
<div itemprop="action" itemscope itemtype="http://schema.org/ViewAction">
  <link itemprop="url" href="https://github.com/mlpack/mlpack/pull/694/files/21d94c04652e8faadd5e8991103a3b73b4c81033..a92afaaafb1af3deede31c1a5ef0b508bfbfe105#r69402370"></link>
  <meta itemprop="name" content="View Pull Request"></meta>
</div>
<meta itemprop="description" content="View this Pull Request on GitHub"></meta>
</div>