Why there is no filter function of Stream in idris? : <p>There is <code>filter : (a -&gt; Bool) -&gt; List a -&gt; List a</code> for List, but there is no <code>filter : (a -&gt; Bool) -&gt; Stream a -&gt; Stream a</code> for Stream, why?</p>

<p>Is there some alternatives to do the similar jobs?</p>
