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<div class="">On 18 May 2016, at 07:38, Will Robertson <<a href="mailto:will@wspr.io" class="">will@wspr.io</a>> wrote:</div>
It should be fine to have something like</blockquote>
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\IfFileExists{luatex85.sty}{\usepackage{luatex85}}{}<br class="">
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for the time being. This should catch 99.999% of users?<br class="">
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This is the macro I am using to find if a file exists and act upon it. Hope this helps.
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<div class=""><font face="Courier" class="">% .... File finding ...........................................................</font></div>
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</font></div>
<div class=""><font face="Courier" class="">% If #1.#2 or #1 exists execute #3{#1} and return \iftrue else only return \iffalse.</font></div>
<div class=""><font face="Courier" class="">% do not forget to close with \fi or with \else...\fi</font></div>
<div class=""><font face="Courier" class="">% Use #3=\gobbleoneargument to effectively kill #3{file}.</font></div>
<div class=""><font face="Courier" class="">% Use #3=\relax to leave file behind.</font></div>
<div class=""><font face="Courier" class="">% Use #3={\def\macrotodefine} to define file as macro content.</font></div>
<div class=""><font face="Courier" class="">\def\iffilewithsuffix#1#2#3{%</font></div>
<div class=""><font face="Courier" class=""><span class="Apple-tab-span" style="white-space:pre"></span>\let\mynext\iftrue</font></div>
<div class=""><font face="Courier" class=""><span class="Apple-tab-span" style="white-space:pre"></span>\doiffileelse{#1.#2}%
<span class="Apple-tab-span" style="white-space:pre"></span>existence of #1.#2 tested</font></div>
<div class=""><font face="Courier" class=""><span class="Apple-tab-span" style="white-space:pre"></span>{#3{#1.#2}}%<span class="Apple-tab-span" style="white-space:pre">
</span>#1.#2 does exist</font></div>
<div class=""><font face="Courier" class=""><span class="Apple-tab-span" style="white-space:pre"></span>{\doiffileelse{#1}%
<span class="Apple-tab-span" style="white-space:pre"></span>existence of #1 tested</font></div>
<div class=""><font face="Courier" class=""><span class="Apple-tab-span" style="white-space:pre"></span>{#3{#1}}%<span class="Apple-tab-span" style="white-space:pre">
</span>#1 exists</font></div>
<div class=""><font face="Courier" class=""><span class="Apple-tab-span" style="white-space:pre"></span>{\let\mynext\iffalse}%<span class="Apple-tab-span" style="white-space:pre">
</span>neither file exists remove macro call</font></div>
<div class=""><font face="Courier" class=""><span class="Apple-tab-span" style="white-space:pre"></span>}%</font></div>
<div class=""><font face="Courier" class=""><span class="Apple-tab-span" style="white-space:pre"></span>\mynext</font></div>
<div class=""><font face="Courier" class="">}</font></div>
<div class=""><font face="Courier" class="">\def\ifexistfilewithsuffix#1#2{%</font></div>
<div class=""><font face="Courier" class=""><span class="Apple-tab-span" style="white-space:pre"></span>\let\mynext\iftrue</font></div>
<div class=""><font face="Courier" class=""><span class="Apple-tab-span" style="white-space:pre"></span>\doifnotfile{#1.#2}{\doifnotfile{#1}{\let\mynext\iffalse}}%</font></div>
<div class=""><font face="Courier" class=""><span class="Apple-tab-span" style="white-space:pre"></span>\mynext</font></div>
<div class=""><font face="Courier" class="">}</font></div>
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<div class="">Hans van der Meer<br class="">
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