I was making the naive assumption that if OP didn&#39;t know about it then it wasn&#39;t prominent. That perhaps was a little hasty. There is a discussion of this very thing in the official user guide. First section, 7.16.1. Syntax.<div>
<br></div><div>Ben</div><br><div>On Tue May 20 2014 at 15:20:54, Brandon Allbery &lt;<a href="mailto:allbery.b@gmail.com">allbery.b@gmail.com</a>&gt; wrote:</div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div dir="ltr"><div class="gmail_extra"><div class="gmail_quote">On Tue, May 20, 2014 at 7:00 AM, <a href="mailto:edwardsbenj@gmail.com" target="_blank">edwardsbenj@gmail.com</a> <span dir="ltr">&lt;<a href="mailto:edwards.benj@gmail.com" target="_blank">edwards.benj@gmail.com</a>&gt;</span> wrote:<br>

<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">This is a known limitation. You can&#39;t refer to items in splices that haven&#39;t already been mentioned in the source. I don&#39;t know why it isn&#39;t (prominently) documented, it&#39;s definitely part of the folklore.</blockquote>

</div><div><br></div></div></div><div dir="ltr"><div class="gmail_extra"><div>I think it&#39;s pretty well documented? At least I recall noting it first time I looked into TH.</div></div></div><div dir="ltr"><div class="gmail_extra">
<div><br></div>-- <br><div dir="ltr"><div>brandon s allbery kf8nh                               sine nomine associates</div>
<div><a href="mailto:allbery.b@gmail.com" target="_blank">allbery.b@gmail.com</a>                                  <a href="mailto:ballbery@sinenomine.net" target="_blank">ballbery@sinenomine.net</a></div><div>unix, openafs, kerberos, infrastructure, xmonad        <a href="http://sinenomine.net" target="_blank">http://sinenomine.net</a></div>

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