preamble.tex

\documentclass[\OPTmodes]{book}

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% Uncomment for diagnostics!
% \usepackage[cam,width=6in,height=9in]{crop}

% Font settings
%--------------------------------------------------------------%  Note:
\usepackage[no-math]{fontspec}                                 %  This exact order
\usepackage{libertine}                                         %  of declarations
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% To use Libertine letters and numbers,
% but tx-style operators in math environment:
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\usepackage{amsmath}
% Needed to display additional math unicode symbols (like double-colon)

% https://github.com/wspr/unicode-math/issues/469
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\usepackage{unicode-math}
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\usepackage[all]{nowidow}
\usepackage{emptypage}
\usepackage{noindentafter}

\usepackage{graphicx}
\usepackage{caption, wrapfig, framed, subfigure}
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\usepackage{titlecaps}

\usepackage[usenames,dvipsnames,x11names]{xcolor}
\usepackage{longtable}
\usepackage{booktabs}
% Workaround to fix mismatched left and right math delimiters. Taken from:
% http://tex.stackexchange.com/questions/63410/parentheses-differ-xelatex-fontspec-newtxmath-libertine
\DeclareSymbolFont{parenthesis}{T1}{fxl}{m}{n}
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% Use tikz-cd for commutative diagrams
\usepackage{tikz-cd}
\usepackage[framemethod=TikZ]{mdframed}

\usepackage{ifthen}
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\usepackage{imakeidx}
\usepackage[totoc,font=footnotesize]{idxlayout}
\usepackage{fancyhdr}
\pagestyle{plain}
\usepackage[final]{pdfpages} % inserts pages from a pdf file

\usepackage{titlesec}  % to change the appearance of section titles
\usepackage{listings}  % for syntax highlighted code listings
\usepackage{enumerate} % allows customized labels in enumerations
\usepackage{enumitem}  % allows nested enumeration with numbers
\PassOptionsToPackage{hyphens}{url}\usepackage{hyperref}  % makes cross references and URLs clickable
\definecolor{LinkRed}{HTML}{80171F}
\hypersetup{
  pdfauthor={Bartosz Milewski},
  pdftitle={Category Theory for Programmers},
  pdfsubject={category theory, computer science, programming, abstraction, composition},
  colorlinks=true,
  linkcolor=LinkRed,
  urlcolor=LinkRed,
}
\usepackage{afterpage}
\newcommand\blankpage{%
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\usepackage{subfiles}
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}
\makeatother

% Document colors
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\definecolor{ChapterGray}   {HTML} {C8C8C8}
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% removes the "Part X" text from \part
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\usepackage{xparse}
\usepackage[abspath]{currfile}

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\newcommand{\urlref}[2]{\href{#1}{#2}\urlfootnote{#1}}

% https://tex.stackexchange.com/questions/219445/line-break-in-texttt/219497
\renewcommand{\code}[1]{%
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\makeatletter
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\setcounter{tocdepth}{3}

\sloppy
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% reduce space between items in a list
\providecommand{\tightlist}{%
\setlength{\itemsep}{0pt}\setlength{\parskip}{0pt}}

%====================%
%  End of preamble.  %
%====================%

\input{category}
\begin{document}