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<div class="moz-cite-prefix">Doug McKenna wrote:<br>
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<blockquote type="cite" cite="mid:859334752.5948473.1578759508071.JavaMail.zimbra@mathemaesthetics.com">
<pre wrap="">Phil Taylor wrote:
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<pre wrap="">| How about delaying the definition of \Umathcode until after
| "load-unicode-data.tex" has been processed ? Is that possible, and
| would it have undesirable side-effects ?
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\Umathcode is a XeTeX primitive extension to the TeX language in the service of solving a problem in classic TeX, which was that the machinery and syntax of the classic TeX \mathchar primitive could not handle 21-bit Unicode values, or more than 16 math font families, etc. So \Umathchar (and a bunch of other related extensions all starting with 'U') is defined in XeTeX's WEB source code; it exists the moment the engine is launched. Thus it's not possible to delay \Umathchar's definition.</pre>
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OK, understood. So because JSBox is required/designed to incorporate all of XeTeX's features, it must (by definition) implement/provide \Umathcode. But could not JSbox perform (or simulate) the following :<br>
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\let \Umathschar = \Umathchar % use British spelling as synonym<br>
\let \Umathchar = \undefined % inhibit "load-unicode-data.tex"'s special treatment of engines that implement \Umathchar<br>
\input load-unicode-data % since it would seem that you cannot simply skip this step<br>
\let \Umathchar = \Umathschar % restore canonical meaning of \Umathchar<br>
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<blockquote type="cite" cite="mid:859334752.5948473.1578759508071.JavaMail.zimbra@mathemaesthetics.com">
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Furthermore, the purpose of executing "load-unicode-data.tex" is precisely to populate the \Umathchar table, as well as other Unicode character tables. So these tables have to exist prior to executing the file. </pre>
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Well, do they, in the case of JSBox ? From what you wrote in your original query, I thought that that [1] was the very thing that you were trying to avoid ...<br>
[1] "executing "load-unicode-data.tex" [in order] to populate the \Umathchar table". So specifically, does the \Umathchar table have to exist, in JSBox, at the point that "load-unicode-data.tex" is loaded ?<br>
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<blockquote type="cite" cite="mid:859334752.5948473.1578759508071.JavaMail.zimbra@mathemaesthetics.com">
<pre wrap="">Perhaps I'm misunderstanding your question.
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OK, I hope that I have now clarified both my query and my proputative posed solution.<br>
<i>Philip Taylor</i><br>
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