latex/listings extend/add to a literate rule

Question

I was looking at this question here Listings: syntax for literate but when I try the mew of the solution, it crashes if I insert special characters like the German ä.

Since these should be escaped by the first literate rule, I assume that the first literate rule is overwritten by the following one.

Is there a way around this? (then it's be possible to specify a literate rule in general for all listings and then just adding to to the literate rule some things for each language)

Answer 1

There must be some clever way just to add to the literate list, but I don't know it. However, just today I had a very similar problem, for Matlab code. I simply went to the mcode.sty file, and copied the entire list of literate replacements, and then added mine. So the old one looked like this

\lstset{%
  literate=%
  {(end)}{\lstbasicfont (end)}{5} % black ``end'' when indexing last vector element
  {({ }end)}{\lstbasicfont ({ }end)}{6}
  {(end{ })}{\lstbasicfont (end{ })}{6}
  {({ }end{ })}{\lstbasicfont ({ }end{ })}{7}
  {:end}{\lstbasicfont :end}{4}
  {:{ }end}{\lstbasicfont :{ }end}{5}
  {end:}{\lstbasicfont end:}{4}
  {end{ }:}{\lstbasicfont end{ }:}{5}
  {,end}{\lstbasicfont ,end}{4}
  {,{ }end}{\lstbasicfont ,{ }end}{5}
  {µ}{$\mu$}1
  {~}{{\fontfamily{ptm}\selectfont\texttildelow}}1 % get a nicer tilde character
  }

and I changed that to

\lstset{%
  literate=%
    {(end)}{\lstbasicfont (end)}{5} % black ``end'' when indexing last vector element
    {({ }end)}{\lstbasicfont ({ }end)}{6}
    {(end{ })}{\lstbasicfont (end{ })}{6}
    {({ }end{ })}{\lstbasicfont ({ }end{ })}{7}
    {:end}{\lstbasicfont :end}{4}
    {:{ }end}{\lstbasicfont :{ }end}{5}
    {end:}{\lstbasicfont end:}{4}
    {end{ }:}{\lstbasicfont end{ }:}{5}
    {,end}{\lstbasicfont ,end}{4}
    {,{ }end}{\lstbasicfont ,{ }end}{5}
    {µ}{$\mu$}1
    {~}{{\fontfamily{ptm}\selectfont\texttildelow}}1 % get a nicer tilde character
    {×}{$\times$}1 % W.E.D. added on 1/18/2021
  }

So, if you can find which package you are using that already defines a literate list, just copy and paste that into your document along with your addition.