Cfrgtkky

As shown below, the code fails to redefine the color when it is white (e.g. rgb(1,1,1)).

documentclass{standalone}

usepackage{tikz}

usepackage{xcolor}

begin{document}

   foreach code/col in {%

   {1,1,1}/white,

   {1,1,0}/yellow,

   {1,0,1}/pink

   }{



   ifx {code} {1,1,1}

   definecolor{tempcolor}{rgb}{1,0,0}

   else

   definecolor{tempcolor}{rgb}{code}

   fi

   textcolor{tempcolor}{col};

   }



end{document}

Why is my condition failing?

REVISION: Your original attempt works almost literally.

documentclass{standalone}

usepackage{tikz}

begin{document}

   edefspeciallist{1,1,1}

   foreach code/col in {%

   {1,1,1}/white,

   {1,1,0}/yellow,

   {1,0,1}/pink

   }{



   ifxcodespeciallist

    definecolor{tempcolor}{rgb}{1,0,0}

   else

    definecolor{tempcolor}{rgb}{code}

   fi

    textcolor{tempcolor}{col};

   }



end{document}

OLDER ANSWER: TikZ comes with all the tools to compare these lists, you do not need to load additional packages. (BTW, you also do not have to load xcolor.) In more detail, TikZ allows you to parse lists (or arrays), and this allows you to define a quantity that is 0 if all entries coincide with your target list and 1 otherwise. In more detail, I compute a quantity

pgfmathtruncatemacro{myx}{sign(abs({code}[0]-{speciallist}[0])+abs({code}[1]-{speciallist}[1])+abs({code}[2]-{speciallist}[2]))}

where

• 
  pgfmathtruncatemacro ensures that one gets an integer, such that ifnum, which only works for integers, works.


• the argument is |first entry of code - first entry of speciallist|+|second entry of code - second entry of speciallist|+|third entry of code - third entry of speciallist|.

Clearly, this quantity is only 0 if all the entries of the lists coincide. Here, {code}[0] evaluates to the first entry of the list code, and so on.

documentclass{standalone}

usepackage{tikz}

begin{document}

   edefspeciallist{1,1,1}

   foreach code/col in {%

   {1,1,1}/white,

   {1,1,0}/yellow,

   {1,0,1}/pink

   }{

   pgfmathtruncatemacro{myx}{sign(abs({code}[0]-{speciallist}[0])+abs({code}[1]-{speciallist}[1])+abs({code}[2]-{speciallist}[2]))}

   ifnummyx=0

    definecolor{tempcolor}{rgb}{1,0,0}

   else

    definecolor{tempcolor}{rgb}{code}

   fi

    textcolor{tempcolor}{col};

   }



end{document}

You're technically hoping to see whether code equals 1,1,1 as a text string. You can use pdfstrcmp{<strA>}{<strB>} for this. It returns -1/0/1 if <strA> is smaller than/equal to/greater than <strB> (lexicographically):

documentclass{article}



usepackage{tikz}



begin{document}



foreach code/col in {%

    {1,1,1}/white,%

    {1,1,0}/yellow,%

    {1,0,1}/pink%

  }{



  ifnumpdfstrcmp{code}{1,1,1}=0

    definecolor{tempcolor}{rgb}{1,0,0}%

  else

    definecolor{tempcolor}{rgb}{code}%

  fi

  textcolor{tempcolor}{col};

}



end{document}