Untitled

\documentclass{article}
\usepackage{tikz}
\usepackage{pifont}
\usepackage{xcolor}
\usetikzlibrary{arrows.meta}
\tikzset{
Mcirc/.style={
  circle,
  inner sep=0pt,
  % text width=1.5em,
  align = center,
  draw = black,
  fill = white
}}
\tikzset{
Mrec/.style={
  rectangle,
  inner sep=0pt,
  % text width=1.5em,
  align = center,
  draw = black,
  fill = white
}}

%% ==> Using Hook
% \NewHook{graphvizx/edge/()}
% \NewHook{graphvizx/edge/[]}
% \NewDocumentCommand{\cmda}{}{Hello \UseHook{graphvizx/edge/[]}}
% \cmda\par
% \AddToHook{graphvizx/edge/[]}{
%   \tikz[baseline=-0.5ex, >=Latex]\draw[->, red] (0, 0) -- (1, 0);
% }
% \cmda


\ExplSyntaxOn
%% ==> Using L3-Regex
% () --> circle
% [] --> rectangle
\seq_new:N \l_draw_seq
\seq_new:N \l_draw_line_seq
\regex_new:N \l_draw_split_regex
\regex_set:Nn \l_draw_split_regex { (-->|\.{3}) }
\cs_new_nopar:Npn \_draw_parse:n #1 {
  % split the input by newline
  \_split_draw_table:n {#1}
  % iterate over each line
  \seq_map_inline:Nn \l_draw_seq {
    \regex_split:NnN \l_draw_split_regex {##1} \l_draw_line_seq 
    \seq_map_inline:Nn \l_draw_line_seq {
      \regex_match_case:nnF {
        {\)}{\_circNum:nn {}{####1}}
        {]}{\_circNum:nn {fill}{####1}}
      }{####1}{
      \regex_match_case:nnF {
          {-->}{\tikz[baseline=-0.75ex, >=Latex]\draw[->, red] (0, 0) -- (.75, 0);}
          {...}{\hspace*{.75cm}}
        }{####1}{\relax}
      }
    }
    % write a newline
    \par
  }
}
\cs_new:Npn \_split_draw_table:n #1{
  \seq_set_split:Nnn \l_draw_seq {\\} {#1}
}
\cs_new_nopar:Npn \_circNum:nn #1#2 {
  % extract digit and style (like "+201\color{red}...")
  \seq_set_split:Nee \l_tmpa_seq {|} {\tl_range:nnn {#2}{2}{-2}}
  \tl_set:Ne \l_tmpa_tl {\seq_item:Nn \l_tmpa_seq {1}}
  \tl_set:Ne \l_tmpb_tl {\seq_item:Nn \l_tmpa_seq {2}}
  \tl_if_eq:nnTF {#1}{fill}{
    {\tl_use:N \l_tmpb_tl \ding{\int_eval:n {181+\l_tmpa_tl}}}
  }{
    {\tl_use:N \l_tmpb_tl \ding{\int_eval:n {171+\l_tmpa_tl}}}
  }
}
\NewDocumentCommand{\Gdiag}{m}{\_draw_parse:n {#1}}
\ExplSyntaxOff





\begin{document}
\Gdiag {
  [4] ... (9|\color{teal}) --> [9] --> [4] --> [1] \\
  (9) --> (8) --> (8) --> [9] --> [4|\color[rgb]{0.1, 0.2, 0.3}] \\
  [3] ... [7] --> [3|\color{purple}] --> (3) --> (9) \\
  (7|\color{orange}) --> (5) --> (5) --> (6) ... [8] \\
  (5) --> (3) --> [4] ... [5|\color{red}] --> (7) \\
  (3) --> [4] ... (7) --> (3|\color{cyan}) --> [0]
}

\end{document}