7

I noticed the following strange behavior of LuaTeX. I am not sure if it is intentional or not.

The minimal example is,

fi f{}i f{i} {f}i f\/i \bye

(This is the complete document, plain TeX, thus no package or whatsoever to effect the results)

Here is the pdfTeX output

enter image description here

Which is as expected.

And here is the LuaTeX output

enter image description here

Grouping using curly braces appears to have no effect at all, i.e, it does not disable the use of ligatures. The log files shows that both pdftex and luatex use exactly the same type1 fonts, as expected. So it is not a thing with handling of Opentype, which I initially suspected. Is this a bug (I think it is) or intended behavior of luatex?

I am using the versions of pdftex and luatex from up-to-date TeXLive 2016

Mico
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Yan Zhou
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1 Answers1

9

From the LuaTeX manual (version 0.95)

enter image description here

Using a kern is the only way, as far as I can see. Either \/ or \kern0pt would do.

egreg
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