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diff --git a/Master/texmf-dist/doc/generic/FAQ-en/html/FAQ-alreadydef.html b/Master/texmf-dist/doc/generic/FAQ-en/html/FAQ-alreadydef.html new file mode 100644 index 00000000000..748ce8e51cc --- /dev/null +++ b/Master/texmf-dist/doc/generic/FAQ-en/html/FAQ-alreadydef.html @@ -0,0 +1,61 @@ +<head> +<title>UK TeX FAQ -- question label alreadydef</title> +</head><body> +<h3>Package reports “command already defined”</h3> +<p/>You load a pair of packages, and the second reports that one of the +commands it defines is already present. For example, both the +<i>txfonts</i> and <i>amsmath</i> define a command <code>\</code><code>iint</code> +(and <code>\</code><code>iiint</code> and so on); so +<blockquote> +<pre> +... +\usepackage{txfonts} +\usepackage{amsmath} +</pre> +</blockquote><p> +produces a string of error messages of the form: +<blockquote> +<pre> +! LaTeX Error: Command \iint already defined. + Or name \end... illegal, see p.192 of the manual. +</pre> + +</blockquote><p> +As a general rule, things that <i>amsmath</i> defines, it defines +well; however, there is a good case for using the <i>txfonts</i> +version of <code>\</code><code>iint</code> — the associated <i>tx</i> fonts have a +double integral symbol that doesn’t need to be “faked” in the way +<i>amsmath</i> does. In the case that you are loading several +symbol packages, every one of which defines the same symbol, you are +likely to experience the problem in a big way (<code>\</code><code>euro</code> is a common +victim). +<p/>There are similar cases where one package redefines another’s command, +but no error occurs because the redefining package doesn’t use +<code>\</code><code>newcommand</code>. Often, in such a case, you only notice the change +because you assume the definition given by the first package. The +<i>amsmath</i>–<i>txfonts</i> packages are just such a pair; +<i>txfonts</i> doesn’t provoke errors. +<p/>You may deal with the problem by saving and restoring the command. +Macro programmers may care to do this for themselves; for the rest of +us, there’s the package <i>savesym</i>. The sequence: +<blockquote> +<pre> +\usepackage{savesym} +\usepackage{amsmath} +\savesymbol{iint} +\usepackage{txfonts} +\restoresymbol{TXF}{iint} +</pre> +</blockquote><p> +does the job; restoring the <i>amsmath</i> version of the command, +and making the <i>txfonts</i> version of the command available as +<code>\</code><code>TXFiint</code>. +<p/>Documentation of <i>savesym</i> doesn’t amount to much: the only +commands are <code>\</code><code>savesymbol</code> and <code>\</code><code>restoresymbol</code>, as noted above. +<dl> +<dt><tt><i>amsmath.sty</i></tt><dd>Part of <a href="ftp://cam.ctan.org/tex-archive/macros/latex/required/amslatex.zip">macros/latex/required/amslatex</a> (<a href="ftp://cam.ctan.org/tex-archive/macros/latex/required/amslatex.tar.gz">gzipped tar</a>, <a href="http://www.tex.ac.uk/tex-archive/macros/latex/required/amslatex/">browse</a>) +<dt><tt><i>savesym.sty</i></tt><dd><a href="ftp://cam.ctan.org/tex-archive/macros/latex/contrib/savesym/savesym.sty">macros/latex/contrib/savesym/savesym.sty</a> +<dt><tt><i>txfonts.sty</i></tt><dd>Part of <a href="ftp://cam.ctan.org/tex-archive/fonts/txfonts.zip">fonts/txfonts</a> (<a href="ftp://cam.ctan.org/tex-archive/fonts/txfonts.tar.gz">gzipped tar</a>, <a href="http://www.tex.ac.uk/tex-archive/fonts/txfonts/">browse</a>) +</dl> +<p/><p>This question on the Web: <a href="http://www.tex.ac.uk/cgi-bin/texfaq2html?label=alreadydef">http://www.tex.ac.uk/cgi-bin/texfaq2html?label=alreadydef</a> +</body> |