\usepackage{xcolor}

%%\usepackage{fontspec}

\usepackage[sc]{mathpazo}

\usepackage{fontspec}

\setmainfont[Ligatures=TeX]{Palatino Linotype}

\usepackage{amssymb}

\usepackage{amsmath}

%\usepackage{menukeys}

\definecolor{darkblue}{rgb}{0,0,0.6}

\usepackage[colorlinks=true,urlcolor=darkblue,linkcolor=darkblue]{hyperref}

\usepackage{soul}

\usepackage{marginnote}

\usepackage{fontawesome5}

%%% for regular expressions and values

\newcommand{\ZERO}{\mbox{\bf 0}}

\newcommand{\ONE}{\mbox{\bf 1}}

\newcommand{\Left}{\textit{Left}}

\newcommand{\Right}{\textit{Right}}

\newcommand{\Der}{\textit{Der}}

\newcommand{\der}{\textit{der}}

\newcommand{\Ders}{\textit{Ders}}

\newcommand{\ders}{\textit{ders}}

\newcommand{\inj}{\textit{inj}}

\newcommand{\nullable}{\textit{nullable}}

%%% url pointers

\newcommand{\hv}[1]{\href{#1}{\faFilm}}

\newcommand{\hr}[1]{\href{#1}{\faHandPointRight[regular]}}

\newcommand{\here}[1]{\marginnote{\href{#1}{\faHandPointRight[regular]}}}

\newcommand{\video}[1]{\marginnote{\href{#1}{\faFilm}}}

\newcommand{\alert}{\reversemarginpar\marginpar{\mbox{}\hfill\textcolor{red}{\faExclamationTriangle}}}

\newcommand{\dn}{\stackrel{\mbox{\scriptsize def}}{=}}

\newcommand{\defn}[1]{\textit{\textbf{#1}}}

\newcommand{\dq}[1]{\mbox{\tt{"}}#1\mbox{\tt{"}}}

\definecolor{codegray}{gray}{0.9}

\makeatletter

\def\fnote{\gdef\@thefnmark{}\@footnotetext}

\makeatother

%% a line after figures

\usepackage{caption}

\DeclareCaptionFormat{custom}

{%

  \textbf{#1#2}#3

  \raisebox{0.5em}{\rule{\textwidth}{0.1mm}}

}

\captionsetup{format=custom}

%\usepackage{float}

%\newcommand{\topfigrule}{\vspace*{1pt}\noindent\rule{\columnwidth}{0.4pt}\vspace{2.6pt}}

%\newcommand{\dblfigrule}{\vspace*{1pt}\noindent\rule{\columnwidth}{0.4pt}\vspace{2.6pt}}

%\newcommand{\botfigrule}{\vspace*{1pt}\noindent\rule{\columnwidth}{0.4pt}\vspace{2.6pt}}

\newcommand{\HEADER}{{\bf Please submit your solutions via email. Please submit 

only PDFs! Every solution should be preceeded by the corresponding 

question text, like:

\begin{center}

\begin{tabular}{ll}

Q$n$: & \ldots a difficult question from me\ldots\\

A:    & \ldots an answer from you \ldots\\

Q$n+1$ & \ldots another difficult question\ldots\\

A:     & \ldots another brilliant answer from you\ldots

\end{tabular}

\end{center}

\noindent Solutions will only be accepted until 20th December! Please send only

one homework per email.}\bigskip}

\newcommand{\POSTSCRIPT}{

{\bf (Optional)} This question is for you to provide 

regular feedback to me: for example

what were the most interesting, least interesting, or confusing 

parts in this lecture? Any problems with my Scala code? Please 

feel free to share any other questions or concerns. Also, all my

material is \st{crap} imperfect. If you have any suggestions for

improvement, I am very grateful to hear.\medskip

If *you* want to share anything (code, videos, links), you are

encouraged to do so. Just drop me an email or send a message to the Forum.} 

% CW deadlines

%\def\cwONE{16 October}

%\def\cwTWO{10 November}  

%\def\cwTHREE{27 November} 

%\def\cwFOUR{14 December}

%\def\cwFIVE{12 January}

%\def\cwONE{2nd January}

%\def\cwTWO{2nd January}  

%\def\cwTHREE{2nd January} 

%\def\cwFOUR{2nd January}

%\def\cwFIVE{2nd January}

\def\cwONE{5th January}

\def\cwTWO{5th January}  

\def\cwTHREE{5th January} 

\def\cwFOUR{5th January}

\def\cwFIVE{5th January}

%%\def\cwISABELLE{11 December}

%%%%%%%%%%%%%%

%% lualatex testing commandline arguments

\newcommand{\luaif}[1]{\ifnum1=\directlua{if #1 then tex.sprint(1) else tex.sprint(0) end} }

\luaif{arg[2] == "sol"}

\newcommand{\solution}[1]{%

  \begin{quote}\sf%

    #1%

  \end{quote}} \else

\newcommand{\solution}[1]{}

\fi