key=value parameters

[Vit Zyka <vit.zyka@seznam.cz>]

Hallo ConTeXters,

I am playing with defining my own macro with key=value parameters. 
Please, consider definition:

   \def\setupField[#1]#2[#3]{\getparameters[Field!#1!][#3]}
   \setupField[name][mykey=value,textwidth=2cm]

If you let ConTeXt to show the values by

   \message{
     <mykey=\getvalue{Field!name!mykey}>
     <textwidth=\getvalue{Field!name!textwidth}>
     <tekstbreedte=\getvalue{Field!name!tekstbreedte}> }

you obtain

   <mykey=value>
   <textwidth=\Field!name!textwidth >
   <tekstbreedte=2cm>

While 'mykey' is OK, predefined keys (like textwidth, text, style, ...) 
lead to undefined parameter, that behave like \relax.

I can imagine next solutions:
1) Do not use predefined keys in my macros, e.g. textWidth instead of
    textwidth [=user unfriendly].
2) Use original (mostly Dutch) keys inside of my macros
    [=developer unfriendly].
3) Define:
      \unprotect
      \def\getparametersALL{\dogetparameters\dosetvalueALL}
      \def\dosetvalueALL#1#2{\@EA\def\csname#1#2\endcsname}
      \protect

    and use:
      \def\setupField[#1]#2[#3]{\getparametersALL[Field!#1!][#3]}
      \setupField[name][mykey=value,textwidth=2cm]
      \message{
        <mykey=\getvalue{Field!name!mykey}>
        <textwidth=\getvalue{Field!name!textwidth}>
        <tekstbreedte=\getvalue{Field!name!tekstbreedte}> }

    it gives:
      <mykey=value>
      <textwidth=2cm>
      <tekstbreedte=\Field!enname!tekstbreedte>

Is there any other (more elegant and not-so-dirty) solution?

Thankx
Vit Zyka