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% Packages
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\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{carol2008}
\pdfinfo{
  /Title (scheme.pdf)
  /Creator (Cheatography)
  /Author (carol2008)
  /Subject (scheme Cheat Sheet)
}

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% 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{scheme Cheat Sheet}}}} \\
    \normalsize{by \textcolor{DarkBackground}{carol2008} via \textcolor{DarkBackground}{\uline{cheatography.com/79007/cs/19204/}}}
\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}carol2008 \\
  \uline{cheatography.com/carol2008} \\
  \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 3rd April, 2019.\\
   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*}{3}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{definition var}}  \tn
% Row 0
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{(define \textless{}var name\textgreater{} \textless{}value\textgreater{})} \tn 
% Row Count 1 (+ 1)
% Row 1
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{(define pi 3.14)} \tn 
% Row Count 2 (+ 1)
% Row 2
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{return:  pi} \tn 
% Row Count 3 (+ 1)
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{definition procedure(func)}}  \tn
% Row 0
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{(define (\textless{}name\textgreater{} \textless{}paras\textgreater{}) \textless{}body\textgreater{})} \tn 
% Row Count 1 (+ 1)
% Row 1
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{(define (factorial n)\{\{nl\}\}~~~~ (if (= n 0) \{\{nl\}\}~~~~1 \{\{nl\}\}~~~~ (* n (factorial (- n 1)))) )} \tn 
% Row Count 5 (+ 4)
% Row 2
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{return: procedure name} \tn 
% Row Count 6 (+ 1)
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{x{3.18528 cm} x{1.79172 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{define list}}  \tn
% Row 0
\SetRowColor{LightBackground}
well-formed list (Linked list) & (cons 1 (cons 2 nil)) \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
construct: cons, first: car, rest: cdr & (cons 1 (cons 2 nil)) \tn 
% Row Count 4 (+ 2)
% Row 2
\SetRowColor{LightBackground}
\mymulticolumn{2}{x{5.377cm}}{(list 1 2)} \tn 
% Row Count 5 (+ 1)
% Row 3
\SetRowColor{white}
None: nil  or'( ) & scm\textgreater{} (null? nil) R:\#t \tn 
% Row Count 7 (+ 2)
% Row 4
\SetRowColor{LightBackground}
\mymulticolumn{2}{x{5.377cm}}{malformed list with . (not linked)} \tn 
% Row Count 8 (+ 1)
% Row 5
\SetRowColor{white}
(define x (cons 1 2)) & x \{\{nl\}\}(1 . 2) \tn 
% Row Count 10 (+ 2)
% Row 6
\SetRowColor{LightBackground}
create a list & 1. cons 2 list 3'( \tn 
% Row Count 12 (+ 2)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\SetRowColor{LightBackground}
\mymulticolumn{2}{x{5.377cm}}{1.(cons 1       (cons 2             (cons 3                   (cons 4 nil)))) \newline equivalent to : \newline (list 1 2 3 4) \newline  \newline 2. (cons 1 2). equivalent to '(1 2).  not (list 1 2)}  \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{define lambda expression}}  \tn
% Row 0
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{(lambda (\textless{}formal-parameters\textgreater{}) \textless{}body\textgreater{})} \tn 
% Row Count 1 (+ 1)
% Row 1
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\mymulticolumn{1}{x{5.377cm}}{((lambda (x y z) (+ x y (square z))) 1 2 3)} \tn 
% Row Count 2 (+ 1)
% Row 2
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{return 12} \tn 
% Row Count 3 (+ 1)
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{Same as using define, just no name. In fact, the following expressions are equivalent: \newline (define (plus4 x) (+ x 4)) \newline (define plus4 (lambda (x) (+ x 4))) \newline  \newline !!! REMEMBER: in lambda, paras are in ( ).}  \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
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\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{p{0.4977 cm} p{0.4977 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{cond expression}}  \tn
% Row 0
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\mymulticolumn{2}{x{5.377cm}}{(cond\{\{nl\}\}~~~~ (\textless{}p1\textgreater{} \textless{}e1\textgreater{}) \{\{nl\}\}~~~~(\textless{}p1\textgreater{} \textless{}e1\textgreater{})\{\{nl\}\}~~~~ ...\{\{nl\}\}~~~~(\textless{}pn\textgreater{} \textless{}en\textgreater{}) \{\{nl\}\}~~~~{[}(else \textless{}else expression\textgreater{}){]})} \tn 
% Row Count 5 (+ 5)
% Row 1
\SetRowColor{white}
\mymulticolumn{2}{x{5.377cm}}{\{\{nl\}\}~~~~} \tn 
% Row Count 6 (+ 1)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
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\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{ex: cond}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/carol2008_1554171140_Picture5.png}}} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
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\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
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\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Let}}  \tn
% Row 0
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\mymulticolumn{1}{x{5.377cm}}{lambda: let} \tn 
% Row Count 1 (+ 1)
% Row 1
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{(let ( ( \textless{}symbol\textgreater{} \textless{}expre1\textgreater{}) \{\{nl\}\}~~~~ ... \{\{nl\}\} ~~~~ ( \textless{}symbol\textgreater{} \textless{}expre2\textgreater{})) \{\{nl\}\} ~~~~\textless{}body\textgreater{})} \tn 
% Row Count 5 (+ 4)
% Row 2
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{Ex: we can use the approximation sin(x) = x for small x, and sin(x) = 3sin(x/3)-4(sin(x/3)\textasciicircum{}3) to approach sin(x) for any x} \tn 
% Row Count 8 (+ 3)
% Row 3
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{(define (sin x)\{\{nl\}\} ~~~~(if (\textless{} x 0.000001) \{\{nl\}\}~~~~~~~~ x \{\{nl\}\}~~~~ ~~~~ (let ((recursive-step (sin(/ x 3))))  \{\{nl\}\} ~~~~ ~~~~~~~~(- ( star{\emph{ 3 recursive-step)\{\{nl\}\}~~~~ ~~~~~~~~~~~~ ( star}} 4 (expt recursive-step 3))))))} \tn 
% Row Count 18 (+ 10)
% Row 4
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{\{\{nl\}\}~~~~} \tn 
% Row Count 19 (+ 1)
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{x{2.58804 cm} x{2.38896 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{Lists of Values1}}  \tn
% Row 0
\SetRowColor{LightBackground}
list can contain any data type & Quoting \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
'(1 2 3) & returns the list (1 2 3) \tn 
% Row Count 4 (+ 2)
% Row 2
\SetRowColor{LightBackground}
'(aa bb cc) & returns the list (aa bb cc) \tn 
% Row Count 6 (+ 2)
% Row 3
\SetRowColor{white}
'(1 bb "hello") & returns different data types \tn 
% Row Count 8 (+ 2)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\SetRowColor{LightBackground}
\mymulticolumn{2}{x{5.377cm}}{1.EVERYTHING in Scheme is a list, even the code. \newline 2. Quoting: to interpret a group of values as a list(instead of as a procedure call), put a single quote in front of them.}  \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{x{1.84149 cm} x{3.13551 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{special values}}  \tn
% Row 0
\SetRowColor{LightBackground}
booleans & \#t \#f False false \tn 
% Row Count 1 (+ 1)
% Row 1
\SetRowColor{white}
symbol ' & ' : don't eval \tn 
% Row Count 2 (+ 1)
% Row 2
\SetRowColor{LightBackground}
? & (even? (quotient 45 2)) R: \#t \tn 
% Row Count 4 (+ 2)
% Row 3
\SetRowColor{white}
= only work for numbers & (= \#t \#t) : error \tn 
% Row Count 6 (+ 2)
% Row 4
\SetRowColor{LightBackground}
(and) & \#t : if you have a partial and, and what value could you and it to, did not change the original value it is true \tn 
% Row Count 11 (+ 5)
% Row 5
\SetRowColor{white}
(or) & \#f \tn 
% Row Count 12 (+ 1)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\SetRowColor{LightBackground}
\mymulticolumn{2}{x{5.377cm}}{1. ' vs " " \newline (define c 'a) \newline if call c, return a. if no (define a 1), (eval c) will return error \newline (define c "a") \newline if call c, return "a" \newline  \newline 2. = only work for numbers \newline (= \#t \#t) : error.  \newline (= '(1) '(1)) error \newline  \newline 3. but (equal? (= '(1) '(1)) return: true}  \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{IF Statement}}  \tn
% Row 0
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{if takes in two required arguments and an optional third argument:} \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{(if \textless{}predicate\textgreater{} \textless{}if-true\textgreater{} {[}if-false{]})} \tn 
% Row Count 3 (+ 1)
% Row 2
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{!! if can do a recursive even at the base case.} \tn 
% Row Count 4 (+ 1)
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{if: python vs scheme \newline 1. scheme eval to a value, python directs the flow \newline 2. scheme: if expression just a single expression for each of \#t and \#f. python: can add more lines \newline 3. scheme: no elif.}  \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{scheme  vs python}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/carol2008_1554148735_Picture2.png}}} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{x{2.93643 cm} x{2.04057 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{List Operation}}  \tn
% Row 0
\SetRowColor{LightBackground}
Define x to be a list of values(bad) & get the first value of x: \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
(define x '(1 2 3)) & (car) \tn 
% Row Count 3 (+ 1)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{p{0.4977 cm} p{0.4977 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{construct a list from individual values}}  \tn
% Row 0
\SetRowColor{LightBackground}
\mymulticolumn{2}{x{5.377cm}}{} \tn 
% Row Count 0 (+ 0)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{ex: concat 2 lists}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/carol2008_1554167223_Picture3.png}}} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{replicate}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/carol2008_1554169796_Picture4.png}}} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{replicate(5,3) \newline {[}5,5,5{]} \newline (replicate 5 3) \newline (5 5 5)}  \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{p{0.9954 cm} x{3.9816 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{other}}  \tn
% Row 0
\SetRowColor{LightBackground}
and & false finder \tn 
% Row Count 1 (+ 1)
% Row 1
\SetRowColor{white}
or & true finder \tn 
% Row Count 2 (+ 1)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}


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

\end{document}