\documentclass[10pt,a4paper]{article}

% Packages
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\usepackage{multicol}           % Allows multicols in tables
\usepackage{tabularx}           % Intelligent column widths
\usepackage{tabulary}           % Used in header and footer
\usepackage{hhline}             % Border under tables
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%\usepackage[utf8x]{inputenc}    % For unicode character support
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\usepackage{colortbl}           % For coloured tables
\usepackage{setspace}           % For line height
\usepackage{lastpage}           % Needed for total page number
\usepackage{seqsplit}           % Splits long words.
%\usepackage{opensans}          % Can't make this work so far. Shame. Would be lovely.
\usepackage[normalem]{ulem}     % For underlining links
% Most of the following are not required for the majority
% of cheat sheets but are needed for some symbol support.
\usepackage{amsmath}            % Symbols
\usepackage{MnSymbol}           % Symbols
\usepackage{wasysym}            % Symbols
%\usepackage[english,german,french,spanish,italian]{babel}              % Languages

% Document Info
\author{{[}deleted{]}}
\pdfinfo{
  /Title (javascript-this-binding-in-depth.pdf)
  /Creator (Cheatography)
  /Author ({[}deleted{]})
  /Subject (JavaScript this binding in-depth Cheat Sheet)
}

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% Commands
\newcommand{\SetRowColor}[1]{\noalign{\gdef\RowColorName{#1}}\rowcolor{\RowColorName}} % Shortcut for row colour
\newcommand{\mymulticolumn}[3]{\multicolumn{#1}{>{\columncolor{\RowColorName}}#2}{#3}} % For coloured multi-cols
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\newcommand{\tn}{\tabularnewline} % Required as custom column type in use

% Font and Colours
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\renewcommand{\familydefault}{\sfdefault}
\color{TextColor}

% Header and Footer
\pagestyle{fancy}
\fancyhead{} % Set header to blank
\fancyfoot{} % Set footer to blank
\fancyhead[L]{
\noindent
\begin{multicols}{3}
\begin{tabulary}{5.8cm}{C}
    \SetRowColor{DarkBackground}
    \vspace{-7pt}
    {\parbox{\dimexpr\textwidth-2\fboxsep\relax}{\noindent
        \hspace*{-6pt}\includegraphics[width=5.8cm]{/web/www.cheatography.com/public/images/cheatography_logo.pdf}}
    }
\end{tabulary}
\columnbreak
\begin{tabulary}{11cm}{L}
    \vspace{-2pt}\large{\bf{\textcolor{DarkBackground}{\textrm{JavaScript this binding in-depth Cheat Sheet}}}} \\
    \normalsize{by \textcolor{DarkBackground}{{[}deleted{]}} via \textcolor{DarkBackground}{\uline{cheatography.com/50355/cs/13903/}}}
\end{tabulary}
\end{multicols}}

\fancyfoot[L]{ \footnotesize
\noindent
\begin{multicols}{3}
\begin{tabulary}{5.8cm}{LL}
  \SetRowColor{FootBackground}
  \mymulticolumn{2}{p{5.377cm}}{\bf\textcolor{white}{Cheatographer}}  \\
  \vspace{-2pt}{[}deleted{]} \\
  \uline{cheatography.com/deleted-50355} \\
  \end{tabulary}
\vfill
\columnbreak
\begin{tabulary}{5.8cm}{L}
  \SetRowColor{FootBackground}
  \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Cheat Sheet}}  \\
   \vspace{-2pt}Not Yet Published.\\
   Updated 12th December, 2017.\\
   Page {\thepage} of \pageref{LastPage}.
\end{tabulary}
\vfill
\columnbreak
\begin{tabulary}{5.8cm}{L}
  \SetRowColor{FootBackground}
  \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Sponsor}}  \\
  \SetRowColor{white}
  \vspace{-5pt}
  %\includegraphics[width=48px,height=48px]{dave.jpeg}
  Measure your website readability!\\
  www.readability-score.com
\end{tabulary}
\end{multicols}}




\begin{document}
\raggedright
\raggedcolumns

% Set font size to small. Switch to any value
% from this page to resize cheat sheet text:
% www.emerson.emory.edu/services/latex/latex_169.html
\footnotesize % Small font.

\begin{multicols*}{2}

\begin{tabularx}{8.4cm}{x{2.96 cm} x{5.04 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{8.4cm}}{\bf\textcolor{white}{5 `this` keyword binging rules}}  \tn
% Row 0
\SetRowColor{LightBackground}
Default binging & `this` points to a global object. Keep in mind: in the strict mode global object is `undefined` \tn 
% Row Count 4 (+ 4)
% Row 1
\SetRowColor{white}
Implicit binding & A "context object" reference gets bound to `this` \tn 
% Row Count 6 (+ 2)
% Row 2
\SetRowColor{LightBackground}
Explicit binding & `this` gets bound to an object of our choice by calling explicitly \seqsplit{`Function.prototype.call()`} or \seqsplit{`Function.prototype.apply()`.} Unfortunately, `this` biding is lost in `=` assignments. \tn 
% Row Count 14 (+ 8)
% Row 3
\SetRowColor{white}
Explicit "hard" binding & "Hard" is just an implementation of the `bind()` pattern/method that addresses problem of `this` context lost in assignments \tn 
% Row Count 19 (+ 5)
% Row 4
\SetRowColor{LightBackground}
`new f()` binding & An object, newly constructed by `new` call, is set as `this` reference in function `f` \tn 
% Row Count 23 (+ 4)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\SetRowColor{LightBackground}
\mymulticolumn{2}{x{8.4cm}}{`this` binding rules apply to how `this` keyword gets evaluated in functions. The rules above are sorted from the most generic to the most specialised. Explicit "soft" binding does not prevent us from losing `this` context}  \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{8.4cm}}{\bf\textcolor{white}{Default binding rule example}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{8.4cm}}{window.engine = "broken"; //global string \newline function startEngine() \{ \newline   console.log(this.engine + " started !"); \newline \}; \newline startEngine(); //"broken started !"} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{8.4cm}}{\bf\textcolor{white}{Implicit binding rule example}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{8.4cm}}{window.engine = "broken"; \newline function startEngine() \{ \newline   console.log(this.engine + " started !"); \newline \}; \newline var raceCar = \{ \newline   engine: "560hp", \newline   startEngine: startEngine \newline \}; \newline raceCar.startEngine(); //"560hp started !"} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{8.4cm}}{\bf\textcolor{white}{Implicit binding rule broken}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{8.4cm}}{function startEngine() \{ \newline   console.log(this.engine + " started !"); \newline \}; \newline var raceCar = \{ \newline   engine: "560hp", \newline   startEngine: startEngine \newline \}; \newline var startRaceCarEngine = raceCar.startEngine; //implicit binding lost ! \newline startRaceCarEngine(); //"undefined started !"} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{8.4cm}}{\bf\textcolor{white}{Explicit rule example}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{8.4cm}}{function startEngine() \{ \newline   console.log(this.engine + " started !"); \newline \} \newline var raceCar = \{ \newline   engine: "560hp" \newline \}; \newline startEngine.call(raceCar); // "560hp started !" \newline startEngine.apply(raceCar); // "560hp started !"} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{8.4cm}}{\bf\textcolor{white}{Explicit binding rule broken}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{8.4cm}}{function startEngine() \{ \newline   return function() \{ \newline     console.log(this.engine + " started !"); \newline   \} \newline \} \newline var raceCar = \{ \newline   engine: "560hp" \newline \}; \newline startEngine.call(raceCar)(); //"undefined started !"} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{8.4cm}}{\bf\textcolor{white}{Explicit "hard" rule example}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{8.4cm}}{function startEngineFactory() \{ \newline   return (function() \{ \newline     console.log(this.engine + " started !"); \newline   \}).bind(raceCar); //"hard" binding ! \newline \} \newline var raceCar = \{ \newline   engine: "560hp" \newline \}; \newline var startEngine = startEngineFactory(); \newline startEngine(\{ engine: "78hp" \});//"560hp started !" \newline startEngine.call(\{ engine: "51hp" \});//"560hp started !"} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{8.4cm}}{no matter what you pass to startEngine() function, it is always bound to raceCar object instance}  \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{8.4cm}}{\bf\textcolor{white}{"New" rule example}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{8.4cm}}{function startEngine(power) \{ \newline   this.engine = power; //a new object \newline \} \newline var slowCar = new startEngine("33hp"); \newline var fastCar = new startEngine("260hp"); \newline console.log(slowCar); //\{engine: "33hp"\} \newline console.log(fastCar); //\{engine: "260hp"\}} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{8.4cm}}{this gets bound to a newly created object (passed as {\emph{this}} to the function body)}  \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{8.4cm}}{\bf\textcolor{white}{All rules in one example}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{8.4cm}}{window.engine = "broken"; \newline function startEngine(power) \{ \newline   var log = this.engine + " preparing... "; \newline   this.engine = power; \newline   console.log(log + this.engine + " started !"); \newline \} \newline var raceCar = \{ \newline   engine: "560hp", \newline   startEngine: startEngine \newline \}; \newline startEngine("15hp"); //default binding \newline raceCar.startEngine("700hp"); //implicit binding \newline startEngine.apply(\{ engine: "{[}to-be-set{]}" \}, {[}"440hp"{]}); //explicit binding \newline var newCar = new startEngine("33hp"); //"new" binding \newline  \newline //logs as follows: \newline //"broken preparing... 15hp started !" \newline //"560hp preparing... 700hp started !" \newline //"{[}to-be-set{]} preparing... 440hp started !" \newline //"undefined preparing... 33hp started !"} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}


% That's all folks
\end{multicols*}

\end{document}