__HEADER__(Some extra math-related symbols.)
% A collection of math-related symbols / tools I often use, mainly collected together from Stack Overflow or hacked together myself

%Dependencies
\RequirePackage{tikz}

% noloc command by
%   user 'egreg' (https://tex.stackexchange.com/users/4427/egreg)
% posted on
%   https://tex.stackexchange.com/questions/546713/spacing-in-colon (Spacing in \colon)
% Prints a mirrored \colon correctly
\RequirePackage{amsmath}
\newcommand\noloc{%
  \nobreak
  \mspace{6mu plus 1mu}
  {:}
  \nonscript\mkern-\thinmuskip
  \mathpunct{}
  \mspace{2mu}
}

% \contra command from Gilles Castel, taken from
%   https://github.com/gillescastel/university-setup/blob/master/preamble.tex
% (retrieved 2021-09-08)
% The preamble linked above is MIT-licensed by Gilles Castel
\RequirePackage{stmaryrd} % for \lightning
\RequirePackage{graphicx}
\newcommand\contra{\scalebox{1.5}{$\lightning$}}

%Print a warning sign
\RequirePackage{pgf}
\newcommand\Warning{%
 \makebox[1.4em][c]{%
 \makebox[0pt][c]{\raisebox{.1em}{\small!}}%
 \makebox[0pt][c]{\color{red}\Large$\bigtriangleup$}}}%

%Make circled symbols
\newcommand*\circled[1]{\tikz[baseline=(char.base)]{
    \node[shape=circle,draw,inner sep=2pt] (char) {#1};}
}

% When dealing with chain complexes, one often uses a bullet as placeholder for the index to mean the whole chain:
\newcommand\chainbullet{\bullet}