<div dir="ltr">trying the following example in Plain TeX,<br><br>%%%%%%%%%%%%%%%%%%%%%%%%%%<br>\input pstricks<br>\input pstricks-add<br>Test<br>\end<br>%%%%%%%%%%%%%%%%%%%%%%%%%<br><br>You will get the following error<br>
<br>%%%%%%%%%%%%%%%%%%%%%%%%%%%<br clear="all">Runaway definition?<br>#1#2#3#4#5-&gt;\expandafter <br>! Forbidden control sequence found while scanning definition of \XKV@d@f@ne@b@o<br>lkey.<br>&lt;inserted text&gt; <br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; }<br>
&lt;to be read again&gt; <br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; \newif <br>l.448&nbsp;&nbsp; \expandafter\newif<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; \csname if#3\endcsname<br>? <br><br>%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%<br>-- <br>VK<br>
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