Bdtjtk

I am attempting to write a music related package where the user can enter chord names, that will be nicely printed:

% this prints out the C chord

somecommand{C}

However, a chord names can have sharps and flats and I want the UI to be as simple as possible. Basically, avoid the need for the user to have to escape the # character, so he can write just this:

somecommand{C#}

instead of this:

somecommand{C#}

In this answer, I read that this can be done with:

catcode`#=12

So this, indeed, works:

documentclass{article}

newcommand{mycommand}[1]

{

   chord=#1

}    

catcode`#=12   

begin{document}

mycommand{G#}

end{document}

And prints "chord=G#".

However, I am unable to make that trick work in the real situation, because all of this is actually embedded into a Tikz environment:

documentclass{article}

usepackage{tikz}



newenvironment{myenv}

{

    newcommand{mycommand}[1]

    {

    draw(0,0) node {chord=##1};

    }

    begin{tikzpicture}

}

{

    end{tikzpicture}

}  



catcode`#=12



begin{document}

begin{myenv}

mycommand{G#}

end{myenv}

end{document}

This MCVE produces lots of errors that I cannot understand:

ABD: EveryShipout initializing macros

(/usr/local/texlive/2017/texmf-dist/tex/context/base/mkii/supp-pdf.mkii

[Loading MPS to PDF converter (version 2006.09.02).]

! Use of @@mptopdf@@newabove doesn't match its definition.

l.136     @@mptopdf@@newabove csname n

                                        ewcountendcsname scratchcounter

If you say, e.g., `defa1{...}', then you must always

put `1' after `a', since control sequence names are

made up of letters only. The macro here has not been

followed by the required stuff, so I'm ignoring it.



! Extra endcsname.

l.136 ...opdf@@newabove csname newcountendcsname

...

Questions:

• Can this be fixed in some way? How?


• Or am I going the wrong way? Is there another path to achieve this goal?

Delay the setting:

documentclass{article}

usepackage{tikz}



newenvironment{myenv}

 {%

  newcommand{mycommand}[1]

    {%

    draw(0,0) node {chord=##1};

    }%

    begin{tikzpicture}

 }

 {%

    end{tikzpicture}%

 }  



AtBeginDocument{catcode`#=12 }



begin{document}

begin{myenv}

mycommand{G#}

end{myenv}

end{document}

It's a bad idea nonetheless. Use G# and your life will be better.

documentclass{article}

usepackage{tikz}



   newcommand{mycommand}[1]

    {

      draw(0,0) node {chord=#1};

    }



newenvironment{myenv}

{

 catcode`#=12

 begin{tikzpicture}

}

{

 end{tikzpicture}

}







begin{document}

begin{myenv}

mycommand{G#}

end{myenv}

end{document}