I noticed that tex4ht do not generate correct code for typesetting Matlab code listing. It does not like .^ in the Matlab code, and it generates funny looking character in its place.
MWE
\documentclass[12pt]{article}%
\usepackage{amsmath,mathtools}
\usepackage[framed,autolinebreaks]{mcode}%
\begin{document}
\begin{lstlisting}
a.^2;
\end{lstlisting}
\end{document}
Compiled used
make4ht --lua -u foo.tex "htm"
This is the HTML generated

<?xml version="1.0" encoding="utf-8" ?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<!--http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd-->
<html xmlns="http://www.w3.org/1999/xhtml">
<head><title></title>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<meta name="generator" content="TeX4ht (http://www.tug.org/tex4ht/)" />
<meta name="originator" content="TeX4ht (http://www.tug.org/tex4ht/)" />
<!-- xhtml,htm,charset=utf-8,html -->
<meta name="src" content="foo.tex" />
<meta name="date" content="2016-01-29 00:44:00" />
<link rel="stylesheet" type="text/css" href="foo.css" />
</head><body>
<!--l. 7-->
<div class="lstlisting" id="listing-1"><span class="label"><a
id="x1-2r1"></a></span><span
class="pcrr8r-">a.</span><span
class="pcrr8r-">Ȉ2;</span>
</div>
</body></html>
I can't used \usepackage[T1]{fontenc} which would have fixed this, since when I used \usepackage[T1]{fontenc} before in other places with tex4ht, it caused many other problems, so I stopped using it. I do not now remember now what the problems were, but were related to some problem with how the HTML looked. When I stopped \usepackage[T1]{fontenc} then, it fixed the HTML. But now I find I need it with mcode.
question is: Is it possible to resolve the above, without using \usepackage[T1]{fontenc}? or must one use \usepackage[T1]{fontenc}?
I use --lua and -u options always with make4ht.
-l,--lua Use lualatex for document compilation
-u,--utf8 For output documents in utf8 encoding
Using TL 2015.
file lists:
*File List*
article.cls 2014/09/29 v1.4h Standard LaTeX document class
size12.clo 2014/09/29 v1.4h Standard LaTeX file (size option)
tex4ht.sty
fontenc.sty
t1enc.def 2005/09/27 v1.99g Standard LaTeX file
t1enc.def 2005/09/27 v1.99g Standard LaTeX file
amsmath.sty 2013/01/14 v2.14 AMS math features
amstext.sty 2000/06/29 v2.01
amsgen.sty 1999/11/30 v2.0
amsgen.sty 1999/11/30 v2.0
amsbsy.sty 1999/11/29 v1.2d
amsopn.sty 1999/12/14 v2.01 operator names
mathtools.sty 2015/11/12 v1.18 mathematical typesetting tools
keyval.sty 2014/10/28 v1.15 key=value parser (DPC)
calc.sty 2014/10/28 v4.3 Infix arithmetic (KKT,FJ)
mhsetup.sty 2010/01/21 v1.2a programming setup (MH)
mcode.sty 2014/03/06 2.5
xcolor.sty 2007/01/21 v2.11 LaTeX color extensions (UK)
color.cfg 2007/01/18 v1.5 color configuration of teTeX/TeXLive
color.cfg 2007/01/18 v1.5 color configuration of teTeX/TeXLive
dvips.def 2014/10/14 v3.0j Driver-dependent file (DPC,SPQR)
dvips.def 2014/10/14 v3.0j Driver-dependent file (DPC,SPQR)
listings.sty 2015/06/04 1.6 (Carsten Heinz)
lstmisc.sty 2015/06/04 1.6 (Carsten Heinz)
lstmisc.sty 2015/06/04 1.6 (Carsten Heinz)
listings.cfg 2015/06/04 1.6 listings configuration
listings.cfg 2015/06/04 1.6 listings configuration
textcomp.sty 2005/09/27 v1.99g Standard LaTeX package
ts1enc.def 2001/06/05 v3.0e (jk/car/fm) Standard LaTeX file
ts1enc.def 2001/06/05 v3.0e (jk/car/fm) Standard LaTeX file
t1pcr.fd 2001/06/04 font definitions for T1/pcr.
t1pcr.fd 2001/06/04 font definitions for T1/pcr.
ts1cmr.fd 2014/09/29 v2.5h Standard LaTeX font definitions
ts1cmr.fd 2014/09/29 v2.5h Standard LaTeX font definitions
graphicx.sty 2014/10/28 v1.0g Enhanced LaTeX Graphics (DPC,SPQR)
graphics.sty 2014/10/28 v1.0p Standard LaTeX Graphics (DPC,SPQR)
trig.sty 1999/03/16 v1.09 sin cos tan (DPC)
graphics.cfg 2010/04/23 v1.9 graphics configuration of TeX Live
graphics.cfg 2010/04/23 v1.9 graphics configuration of TeX Live

This code compiles fine:exactly as is, but changed the matlab code line. I found big problem with the generated code in HTML. Do you want me to post this as separate question in this case or send it to tex4ht mailing list? The problem shows up when using--luaoption again with make4ht. Using same code you have above. Thanks. – Nasser Feb 26 '16 at 16:28