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% Document Info
\author{Li Donghua (Donghua Li)}
\pdfinfo{
  /Title (rxswift-operators.pdf)
  /Creator (Cheatography)
  /Author (Li Donghua (Donghua Li))
  /Subject (RxSwift Operators Cheat Sheet)
}

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\noindent
\begin{multicols}{3}
\begin{tabulary}{5.8cm}{C}
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    {\parbox{\dimexpr\textwidth-2\fboxsep\relax}{\noindent
        \hspace*{-6pt}\includegraphics[width=5.8cm]{/web/www.cheatography.com/public/images/cheatography_logo.pdf}}
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\begin{tabulary}{11cm}{L}
    \vspace{-2pt}\large{\bf{\textcolor{DarkBackground}{\textrm{RxSwift Operators Cheat Sheet}}}} \\
    \normalsize{by \textcolor{DarkBackground}{Li Donghua (Donghua Li)} via \textcolor{DarkBackground}{\uline{cheatography.com/24671/cs/6169/}}}
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\noindent
\begin{multicols}{3}
\begin{tabulary}{5.8cm}{LL}
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  \mymulticolumn{2}{p{5.377cm}}{\bf\textcolor{white}{Cheatographer}}  \\
  \vspace{-2pt}Li Donghua (Donghua Li) \\
  \uline{cheatography.com/donghua-li} \\
        \uline{\seqsplit{lidonghua}.com}
  \end{tabulary}
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  \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Cheat Sheet}}  \\
   \vspace{-2pt}Published 24th November, 2015.\\
   Updated 13th May, 2016.\\
   Page {\thepage} of \pageref{LastPage}.
\end{tabulary}
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  \vspace{-5pt}
  %\includegraphics[width=48px,height=48px]{dave.jpeg}
  Measure your website readability!\\
  www.readability-score.com
\end{tabulary}
\end{multicols}}




\begin{document}
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\begin{multicols*}{2}

\begin{tabularx}{8.4cm}{x{2.4 cm} x{5.6 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{8.4cm}}{\bf\textcolor{white}{Creating Observables}}  \tn
% Row 0
\SetRowColor{LightBackground}
{\bf{asObservable}} & convert various objects into Observables \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
{\bf{create}} & create an Observable from scratch \tn 
% Row Count 4 (+ 2)
% Row 2
\SetRowColor{LightBackground}
{\bf{deferred}} & create an Observable for each subscription \tn 
% Row Count 6 (+ 2)
% Row 3
\SetRowColor{white}
{\bf{from}} (array) & convert an array into Observable \tn 
% Row Count 8 (+ 2)
% Row 4
\SetRowColor{LightBackground}
\mymulticolumn{2}{x{8.4cm}}{{\bf{of}}} \tn 
% Row Count 9 (+ 1)
% Row 5
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{\bf{empty}} & emit no items; terminates normally \tn 
% Row Count 11 (+ 2)
% Row 6
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{\bf{error}} & emit no items; terminates with an error \tn 
% Row Count 13 (+ 2)
% Row 7
\SetRowColor{white}
{\bf{never}} & emit no items; does not terminate \tn 
% Row Count 15 (+ 2)
% Row 8
\SetRowColor{LightBackground}
{\bf{interval}} & emit a sequence of integers spaced by a given time interval \tn 
% Row Count 18 (+ 3)
% Row 9
\SetRowColor{white}
{\bf{just}} & emit a particular item \tn 
% Row Count 19 (+ 1)
% Row 10
\SetRowColor{LightBackground}
{\bf{range}} & emit a particular range of sequential integers \tn 
% Row Count 21 (+ 2)
% Row 11
\SetRowColor{white}
{\bf{repeatElement}} & emit a particular item multiple times \tn 
% Row Count 23 (+ 2)
% Row 12
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{\bf{timer}} & emit a particular item after a given delay \tn 
% Row Count 25 (+ 2)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
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\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{x{2.4 cm} x{5.6 cm} }
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% Row 0
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{\bf{merge}} & combine multiple Observables into one by merging their emissions \tn 
% Row Count 3 (+ 3)
% Row 1
\SetRowColor{white}
{\bf{startWith}} & emit a specified sequence of items before others from source \tn 
% Row Count 6 (+ 3)
% Row 2
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{\bf{switchLatest}} & convert an Observable that emits Observables into a single Observable that emits the items emitted by the most-recently-emitted of those Observables \tn 
% Row Count 12 (+ 6)
% Row 3
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{\bf{combineLatest}} & combine the latest item emitted by each Observable \tn 
% Row Count 14 (+ 2)
% Row 4
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{\bf{zip}} & combine the emissions of multiple Observables together \tn 
% Row Count 16 (+ 2)
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\begin{tabularx}{8.4cm}{x{3.76 cm} x{4.24 cm} }
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\mymulticolumn{2}{x{8.4cm}}{\bf\textcolor{white}{Observable Utility Operators}}  \tn
% Row 0
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{\bf{delaySubscription}} & shift the emissions forward in time by a particular amount \tn 
% Row Count 3 (+ 3)
% Row 1
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{\bf{do}} / {\bf{doOnNext}} & register an action to take upon Observable lifecycle events \tn 
% Row Count 6 (+ 3)
% Row 2
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{\bf{observeOn}} / {\bf{observeSingleOn}} & specify the Scheduler on which an observer will observe \tn 
% Row Count 9 (+ 3)
% Row 3
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{\bf{subscribe}} & operate upon the emissions and notifications from an Observable \tn 
% Row Count 12 (+ 3)
% Row 4
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{\bf{subscribeOn}} & specify the Scheduler on which an Observable will operate \tn 
% Row Count 15 (+ 3)
% Row 5
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{\bf{timeout}} & abort when no item emitted during a specified span of time \tn 
% Row Count 18 (+ 3)
% Row 6
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% Row Count 22 (+ 4)
% Row 7
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% Row Count 23 (+ 1)
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% Row Count 1 (+ 1)
% Row 1
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% Row Count 3 (+ 2)
% Row 2
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% Row Count 6 (+ 3)
% Row 3
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{\bf{replay}} & ensure that all observers see the same sequence of emitted items \tn 
% Row Count 9 (+ 3)
% Row 4
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% Row Count 10 (+ 1)
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% Row 0
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% Row Count 2 (+ 2)
% Row 1
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% Row 2
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% Row Count 6 (+ 1)
% Row 3
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% Row Count 7 (+ 1)
% Row 4
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{\bf{map}} & transform the items by an Observablapplying a function to each item \tn 
% Row Count 10 (+ 3)
% Row 5
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{\bf{scan}} & apply a function to each item sequentially, and emit each successive value \tn 
% Row Count 13 (+ 3)
% Row 6
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{\bf{window}} & periodically subdivide items into Observables \tn 
% Row Count 15 (+ 2)
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\begin{tabularx}{8.4cm}{x{3.2 cm} x{4.8 cm} }
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% Row 0
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{\bf{debounce}} / {\bf{throttle}} & filters out items rapidly followed by another item \tn 
% Row Count 3 (+ 3)
% Row 1
\SetRowColor{white}
{\bf{distinctUntilChanged}} & suppress duplicate items \tn 
% Row Count 5 (+ 2)
% Row 2
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{\bf{elementAt}} & emit only item {\emph{n}} \tn 
% Row Count 6 (+ 1)
% Row 3
\SetRowColor{white}
{\bf{filter}} & emit only those items that pass a predicate test \tn 
% Row Count 8 (+ 2)
% Row 4
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{\bf{sample}} & emit the most recent items since the previous sampling \tn 
% Row Count 11 (+ 3)
% Row 5
\SetRowColor{white}
{\bf{skip}} & suppress the first {\emph{n}} items \tn 
% Row Count 13 (+ 2)
% Row 6
\SetRowColor{LightBackground}
{\bf{take}} & emit only the first {\emph{n}} items \tn 
% Row Count 15 (+ 2)
% Row 7
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{\bf{takeLast}} & emit only the final {\emph{n}} items \tn 
% Row Count 17 (+ 2)
% Row 8
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{\bf{single}} & emit only the first item \tn 
% Row Count 18 (+ 1)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
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\begin{tabularx}{8.4cm}{x{2 cm} x{6 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{8.4cm}}{\bf\textcolor{white}{Conditional and Boolean Operators}}  \tn
% Row 0
\SetRowColor{LightBackground}
{\bf{amb}} & emit all of the items from only the first to emit an item or notification \tn 
% Row Count 3 (+ 3)
% Row 1
\SetRowColor{white}
{\bf{skipWhile}} & discard items until a specified condition becomes false \tn 
% Row Count 5 (+ 2)
% Row 2
\SetRowColor{LightBackground}
{\bf{skipUntil}} & discard items until a second Observable emits an item \tn 
% Row Count 7 (+ 2)
% Row 3
\SetRowColor{white}
{\bf{takeWhile}} & mirror items until a specified condition becomes false \tn 
% Row Count 9 (+ 2)
% Row 4
\SetRowColor{LightBackground}
{\bf{takeUntil}} & discard any items after a second Observable emits an item or terminates \tn 
% Row Count 12 (+ 3)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
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\par\addvspace{1.3em}

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\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{8.4cm}}{\bf\textcolor{white}{Error Handling Operators}}  \tn
% Row 0
\SetRowColor{LightBackground}
{\bf{catch}} & recover from error by continuing the sequence without error \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
{\bf{retry}} & resubscribe to source when error \tn 
% Row Count 4 (+ 2)
% Row 2
\SetRowColor{LightBackground}
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% Row Count 5 (+ 1)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
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\begin{tabularx}{8.4cm}{x{3.12 cm} x{4.88 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{8.4cm}}{\bf\textcolor{white}{Mathematical and Aggregate Operators}}  \tn
% Row 0
\SetRowColor{LightBackground}
{\bf{concat}} & emit the emissions from two or more Observables without interleaving them \tn 
% Row Count 4 (+ 4)
% Row 1
\SetRowColor{white}
{\bf{reduce}} / {\bf{aggregate}} & apply a function to each item sequentially, and emit the final value \tn 
% Row Count 7 (+ 3)
% Row 2
\SetRowColor{LightBackground}
{\bf{toArray}} & convert an Observable into an array \tn 
% Row Count 9 (+ 2)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}


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

\end{document}