u don't want to consume ends of lines, only
spaces and tabs, you can do it like this:</p>

<pre class="rust rust-example-rendered">
<span class="macro">named</span><span class="macro">!</span>(<span class="kw">pub</span> <span class="ident">space</span>, <span class="macro">eat_separator</span><span class="macro">!</span>(<span class="kw-2">&amp;</span><span class="string">b&quot; \t&quot;</span>[..]));

<span class="attribute">#[<span class="ident">macro_export</span>]</span>
<span class="macro">macro_rule