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diff --git a/Master/texmf-doc/doc/english/FAQ-en/html/FAQ-subverttoks.html b/Master/texmf-doc/doc/english/FAQ-en/html/FAQ-subverttoks.html deleted file mode 100644 index 6becedead22..00000000000 --- a/Master/texmf-doc/doc/english/FAQ-en/html/FAQ-subverttoks.html +++ /dev/null @@ -1,42 +0,0 @@ -<head> -<title>UK TeX FAQ -- question label subverttoks</title> -</head><body> -<h3>Subverting a token register</h3> -<p/>A common requirement is to “subvert” a token register that other -macros may use. The requirement arises when you want to add something -to a system token register (<code>\</code><code>output</code> or <code>\</code><code>every*</code>), but know -that other macros use the token register, too. (A common requirement -is to work on <code>\</code><code>everypar</code>, but LaTeX changes <code>\</code><code>everypar</code> at -every touch and turn.) -<p/>The following technique, due to David Kastrup, does what you need, and -allows an independent package to play the exact same game: -<blockquote> -<pre> -\let\mypkg@@everypar\everypar -\newtoks\mypkg@everypar -\mypkg@everypar\expandafter{\the\everypar} -\mypkg@@everypar{\mypkgs@ownstuff\the\mypkg@everypar} -\def\mypkgs@ownstuff{% - <stuff to do at the start of the token register>% -} -\let\everypar\mypkg@everypar -</pre> - -</blockquote><p> -As you can see, the package (<i>mypkg</i>) -<ul> -<li> creates an alias for the existing “system” <code>\</code><code>everypar</code> - (which is frozen into any surrounding environment, which will carry - on using the original); -<li> creates a token register to subvert <code>\</code><code>everypar</code> and - initialises it with the current contents of <code>\</code><code>everypar</code>; -<li> sets the “old” <code>\</code><code>everypar</code> to execute its own extra code, - as well as the contents of its own token register; -<li> defines the macro for the extra code; and -<li> points the token <code>\</code><code>everypar</code> at the new token register. -</ul> -and away we go. -<p/>The form <code>\</code><code>mypkg@...</code> is (sort of) blessed for LaTeX package -internal names, which is why this example uses macros of that form. -<p/><p>This question on the Web: <a href="http://www.tex.ac.uk/cgi-bin/texfaq2html?label=subverttoks">http://www.tex.ac.uk/cgi-bin/texfaq2html?label=subverttoks</a> -</body> |