[luatex] What's wrong with LuaTeX v0.95.0?

[Joseph Wright]

On 15/05/2016 08:37, Vafa Khalighi wrote:
> Hi
> 
> I have been a lollipop user (http://ctan.org/pkg/lollipop) since 15 years
> ago and its developer from April 2014. For the past 15 years, I have only
> been using Knuth's TeX engine since that gives me all I want. If you try to
> build the lollipop format for Knuth's TeX by:
> 
> tex -ini   -jobname=lollipop -progname=lollipop lollipop.ini
> 
> 
> and process the following minimal example with lollipop format:
> 
> 
> \Start
> 
> Let's say $x$ is a variable
> 
> \Stop
> 
> You see no problem in the output. However, if you build the format by
> using luatex v0.95.0 by
> 
> 
> luatex -ini   -jobname=lollipop -progname=lollipop lollipop.ini
> 
> 
> and process the same file, then the x in the inline math mode
> disappears. Should not luatex at least behave like Knuth's TeX engine?
> Does anyone know what is wrong here?
> 
> The content of my lollipop.ini is
> 
> \scrollmode
> \input lollipop
> \dump
> \endinput
> 
> 
> Vafa
> 

There've been some changes in the internals of handling \Umathcode,
which at least in LaTeX terms requires some updates to parts of the
codebase. What I notice here is that the \Umathcode for 'x' is certainly
wrong, and doing

% Set up extra primitives
\ifx\directlua\undefined\else
  \directlua{tex.enableprimitives("",tex.extraprimitives())}%
\fi
% Direct PDF output for convenience
\ifx\pdfouput\undefined
  \outputmode=1 %
\else
  \pdfoutput=1 %
\fi

\Start

\Umathcodenum`x=31457400 %

%\showtokens\expandafter{\the\Umathcode`\x }%
Let's say $x$ is a variable

\Stop

works.

Joseph