A {\itshape very} minimal implementation of a \href{https://nodejs.org/api/stream.html\#stream_class_stream_passthrough}{\texttt{ Pass\+Through stream}}

\href{https://docs.google.com/spreadsheets/d/1oObKSrVwLX_7Ut4Z6g3fZW-AX1j1-k6w-cDsrkaSbHM/edit\#gid=0}{\texttt{ It\textquotesingle{}s very fast}} for objects, strings, and buffers.

Supports pipe()ing (including multi-\/pipe() and backpressure transmission), buffering data until either a {\ttfamily data} event handler or {\ttfamily pipe()} is added (so you don\textquotesingle{}t lose the first chunk), and most other cases where Pass\+Through is a good idea.

There is a {\ttfamily read()} method, but it\textquotesingle{}s much more efficient to consume data from this stream via `\textquotesingle{}data'{\ttfamily events or by calling}pipe(){\ttfamily into some other stream. Calling}read()\`{} requires the buffer to be flattened in some cases, which requires copying memory.

There is also no {\ttfamily unpipe()} method. Once you start piping, there is no stopping it!

If you set {\ttfamily object\+Mode\+: true} in the options, then whatever is written will be emitted. Otherwise, it\textquotesingle{}ll do a minimal amount of Buffer copying to ensure proper Streams semantics when {\ttfamily read(n)} is called.

{\ttfamily object\+Mode} can also be set by doing {\ttfamily stream.\+object\+Mode = true}, or by writing any non-\/string/non-\/buffer data. {\ttfamily object\+Mode} cannot be set to false once it is set.

This is not a {\ttfamily through} or {\ttfamily through2} stream. It doesn\textquotesingle{}t transform the data, it just passes it right through. If you want to transform the data, extend the class, and override the {\ttfamily write()} method. Once you\textquotesingle{}re done transforming the data however you want, call {\ttfamily super.\+write()} with the transform output.

For some examples of streams that extend Minipass in various ways, check out\+:


\begin{DoxyItemize}
\item \href{http://npm.im/minizlib}{\texttt{ minizlib}}
\item \href{http://npm.im/fs-minipass}{\texttt{ fs-\/minipass}}
\item \href{http://npm.im/tar}{\texttt{ tar}}
\item \href{http://npm.im/minipass-collect}{\texttt{ minipass-\/collect}}
\item \href{http://npm.im/minipass-flush}{\texttt{ minipass-\/flush}}
\item \href{http://npm.im/minipass-pipeline}{\texttt{ minipass-\/pipeline}}
\item \href{http://npm.im/tap}{\texttt{ tap}}
\item \href{http://npm.im/tap}{\texttt{ tap-\/parser}}
\item \href{http://npm.im/tap}{\texttt{ treport}}
\item \href{http://npm.im/minipass-fetch}{\texttt{ minipass-\/fetch}}
\item \href{http://npm.im/pacote}{\texttt{ pacote}}
\item \href{http://npm.im/make-fetch-happen}{\texttt{ make-\/fetch-\/happen}}
\item \href{http://npm.im/cacache}{\texttt{ cacache}}
\item \href{http://npm.im/ssri}{\texttt{ ssri}}
\item \href{http://npm.im/npm-registry-fetch}{\texttt{ npm-\/registry-\/fetch}}
\item \href{http://npm.im/minipass-json-stream}{\texttt{ minipass-\/json-\/stream}}
\item \href{http://npm.im/minipass-sized}{\texttt{ minipass-\/sized}}
\end{DoxyItemize}\hypertarget{md_sfcode_node_modules_minipass_README_autotoc_md17624}{}\doxysection{Differences from Node.\+js Streams}\label{md_sfcode_node_modules_minipass_README_autotoc_md17624}
There are several things that make Minipass streams different from (and in some ways superior to) Node.\+js core streams.

Please read these caveats if you are familiar with noode-\/core streams and intend to use Minipass streams in your programs.\hypertarget{md_sfcode_node_modules_minipass_README_autotoc_md17625}{}\doxysubsection{Timing}\label{md_sfcode_node_modules_minipass_README_autotoc_md17625}
Minipass streams are designed to support synchronous use-\/cases. Thus, data is emitted as soon as it is available, always. It is buffered until read, but no longer. Another way to look at it is that Minipass streams are exactly as synchronous as the logic that writes into them.

This can be surprising if your code relies on {\ttfamily Pass\+Through.\+write()} always providing data on the next tick rather than the current one, or being able to call {\ttfamily resume()} and not have the entire buffer disappear immediately.

However, without this synchronicity guarantee, there would be no way for Minipass to achieve the speeds it does, or support the synchronous use cases that it does. Simply put, waiting takes time.

This non-\/deferring approach makes Minipass streams much easier to reason about, especially in the context of Promises and other flow-\/control mechanisms.\hypertarget{md_sfcode_node_modules_minipass_README_autotoc_md17626}{}\doxysubsection{No High/\+Low Water Marks}\label{md_sfcode_node_modules_minipass_README_autotoc_md17626}
Node.\+js core streams will optimistically fill up a buffer, returning {\ttfamily true} on all writes until the limit is hit, even if the data has nowhere to go. Then, they will not attempt to draw more data in until the buffer size dips below a minimum value.

Minipass streams are much simpler. The {\ttfamily write()} method will return {\ttfamily true} if the data has somewhere to go (which is to say, given the timing guarantees, that the data is already there by the time {\ttfamily write()} returns).

If the data has nowhere to go, then {\ttfamily write()} returns false, and the data sits in a buffer, to be drained out immediately as soon as anyone consumes it.\hypertarget{md_sfcode_node_modules_minipass_README_autotoc_md17627}{}\doxysubsection{Hazards of Buffering (or\+: Why Minipass Is So Fast)}\label{md_sfcode_node_modules_minipass_README_autotoc_md17627}
Since data written to a Minipass stream is immediately written all the way through the pipeline, and {\ttfamily write()} always returns true/false based on whether the data was fully flushed, backpressure is communicated immediately to the upstream caller. This minimizes buffering.

Consider this case\+:


\begin{DoxyCode}{0}
\DoxyCodeLine{const \{PassThrough\} = require('stream')}
\DoxyCodeLine{const p1 = new PassThrough(\{ highWaterMark: 1024 \})}
\DoxyCodeLine{const p2 = new PassThrough(\{ highWaterMark: 1024 \})}
\DoxyCodeLine{const p3 = new PassThrough(\{ highWaterMark: 1024 \})}
\DoxyCodeLine{const p4 = new PassThrough(\{ highWaterMark: 1024 \})}
\DoxyCodeLine{}
\DoxyCodeLine{p1.pipe(p2).pipe(p3).pipe(p4)}
\DoxyCodeLine{p4.on('data', () => console.log('made it through'))}
\DoxyCodeLine{}
\DoxyCodeLine{// this returns false and buffers, then writes to p2 on next tick (1)}
\DoxyCodeLine{// p2 returns false and buffers, pausing p1, then writes to p3 on next tick (2)}
\DoxyCodeLine{// p3 returns false and buffers, pausing p2, then writes to p4 on next tick (3)}
\DoxyCodeLine{// p4 returns false and buffers, pausing p3, then emits 'data' and 'drain'}
\DoxyCodeLine{// on next tick (4)}
\DoxyCodeLine{// p3 sees p4's 'drain' event, and calls resume(), emitting 'resume' and}
\DoxyCodeLine{// 'drain' on next tick (5)}
\DoxyCodeLine{// p2 sees p3's 'drain', calls resume(), emits 'resume' and 'drain' on next tick (6)}
\DoxyCodeLine{// p1 sees p2's 'drain', calls resume(), emits 'resume' and 'drain' on next}
\DoxyCodeLine{// tick (7)}
\DoxyCodeLine{}
\DoxyCodeLine{p1.write(Buffer.alloc(2048)) // returns false }

\end{DoxyCode}


Along the way, the data was buffered and deferred at each stage, and multiple event deferrals happened, for an unblocked pipeline where it was perfectly safe to write all the way through!

Furthermore, setting a {\ttfamily high\+Water\+Mark} of {\ttfamily 1024} might lead someone reading the code to think an advisory maximum of 1KiB is being set for the pipeline. However, the actual advisory buffering level is the {\itshape sum} of {\ttfamily high\+Water\+Mark} values, since each one has its own bucket.

Consider the Minipass case\+:


\begin{DoxyCode}{0}
\DoxyCodeLine{const m1 = new Minipass()}
\DoxyCodeLine{const m2 = new Minipass()}
\DoxyCodeLine{const m3 = new Minipass()}
\DoxyCodeLine{const m4 = new Minipass()}
\DoxyCodeLine{}
\DoxyCodeLine{m1.pipe(m2).pipe(m3).pipe(m4)}
\DoxyCodeLine{m4.on('data', () => console.log('made it through'))}
\DoxyCodeLine{}
\DoxyCodeLine{// m1 is flowing, so it writes the data to m2 immediately}
\DoxyCodeLine{// m2 is flowing, so it writes the data to m3 immediately}
\DoxyCodeLine{// m3 is flowing, so it writes the data to m4 immediately}
\DoxyCodeLine{// m4 is flowing, so it fires the 'data' event immediately, returns true}
\DoxyCodeLine{// m4's write returned true, so m3 is still flowing, returns true}
\DoxyCodeLine{// m3's write returned true, so m2 is still flowing, returns true}
\DoxyCodeLine{// m2's write returned true, so m1 is still flowing, returns true}
\DoxyCodeLine{// No event deferrals or buffering along the way!}
\DoxyCodeLine{}
\DoxyCodeLine{m1.write(Buffer.alloc(2048)) // returns true }

\end{DoxyCode}


It is extremely unlikely that you {\itshape don\textquotesingle{}t} want to buffer any data written, or {\itshape ever} buffer data that can be flushed all the way through. Neither node-\/core streams nor Minipass ever fail to buffer written data, but node-\/core streams do a lot of unnecessary buffering and pausing.

As always, the faster implementation is the one that does less stuff and waits less time to do it.\hypertarget{md_sfcode_node_modules_minipass_README_autotoc_md17628}{}\doxysubsection{Immediately emit $<$tt$>$end$<$/tt$>$ for empty streams (when not paused)}\label{md_sfcode_node_modules_minipass_README_autotoc_md17628}
If a stream is not paused, and {\ttfamily end()} is called before writing any data into it, then it will emit {\ttfamily end} immediately.

If you have logic that occurs on the {\ttfamily end} event which you don\textquotesingle{}t want to potentially happen immediately (for example, closing file descriptors, moving on to the next entry in an archive parse stream, etc.) then be sure to call {\ttfamily stream.\+pause()} on creation, and then {\ttfamily stream.\+resume()} once you are ready to respond to the {\ttfamily end} event.\hypertarget{md_sfcode_node_modules_minipass_README_autotoc_md17629}{}\doxysubsection{Emit $<$tt$>$end$<$/tt$>$ When Asked}\label{md_sfcode_node_modules_minipass_README_autotoc_md17629}
One hazard of immediately emitting `\textquotesingle{}end'\`{} is that you may not yet have had a chance to add a listener. In order to avoid this hazard, Minipass streams safely re-\/emit the `\textquotesingle{}end'{\ttfamily event if a new listener is added after }\textquotesingle{}end\textquotesingle{}\`{} has been emitted.

Ie, if you do `stream.\+on(\textquotesingle{}end', some\+Function){\ttfamily , and the stream has already emitted}end{\ttfamily , then it will call the handler right away. (You can think of this somewhat like attaching a new}.then(fn)\`{} to a previously-\/resolved Promise.)

To prevent calling handlers multiple times who would not expect multiple ends to occur, all listeners are removed from the `\textquotesingle{}end'\`{} event whenever it is emitted.\hypertarget{md_sfcode_node_modules_minipass_README_autotoc_md17630}{}\doxysubsection{Impact of \char`\"{}immediate flow\char`\"{} on Tee-\/streams}\label{md_sfcode_node_modules_minipass_README_autotoc_md17630}
A \char`\"{}tee stream\char`\"{} is a stream piping to multiple destinations\+:


\begin{DoxyCode}{0}
\DoxyCodeLine{const tee = new Minipass()}
\DoxyCodeLine{t.pipe(dest1)}
\DoxyCodeLine{t.pipe(dest2)}
\DoxyCodeLine{t.write('foo') // goes to both destinations }

\end{DoxyCode}


Since Minipass streams {\itshape immediately} process any pending data through the pipeline when a new pipe destination is added, this can have surprising effects, especially when a stream comes in from some other function and may or may not have data in its buffer.


\begin{DoxyCode}{0}
\DoxyCodeLine{// WARNING! WILL LOSE DATA!}
\DoxyCodeLine{const src = new Minipass()}
\DoxyCodeLine{src.write('foo')}
\DoxyCodeLine{src.pipe(dest1) // 'foo' chunk flows to dest1 immediately, and is gone}
\DoxyCodeLine{src.pipe(dest2) // gets nothing! }

\end{DoxyCode}


The solution is to create a dedicated tee-\/stream junction that pipes to both locations, and then pipe to {\itshape that} instead.


\begin{DoxyCode}{0}
\DoxyCodeLine{// Safe example: tee to both places}
\DoxyCodeLine{const src = new Minipass()}
\DoxyCodeLine{src.write('foo')}
\DoxyCodeLine{const tee = new Minipass()}
\DoxyCodeLine{tee.pipe(dest1)}
\DoxyCodeLine{tee.pipe(dest2)}
\DoxyCodeLine{src.pipe(tee) // tee gets 'foo', pipes to both locations }

\end{DoxyCode}


The same caveat applies to `on(\textquotesingle{}data')\`{} event listeners. The first one added will {\itshape immediately} receive all of the data, leaving nothing for the second\+:


\begin{DoxyCode}{0}
\DoxyCodeLine{// WARNING! WILL LOSE DATA!}
\DoxyCodeLine{const src = new Minipass()}
\DoxyCodeLine{src.write('foo')}
\DoxyCodeLine{src.on('data', handler1) // receives 'foo' right away}
\DoxyCodeLine{src.on('data', handler2) // nothing to see here! }

\end{DoxyCode}


Using a dedicated tee-\/stream can be used in this case as well\+:


\begin{DoxyCode}{0}
\DoxyCodeLine{// Safe example: tee to both data handlers}
\DoxyCodeLine{const src = new Minipass()}
\DoxyCodeLine{src.write('foo')}
\DoxyCodeLine{const tee = new Minipass()}
\DoxyCodeLine{tee.on('data', handler1)}
\DoxyCodeLine{tee.on('data', handler2)}
\DoxyCodeLine{src.pipe(tee) }

\end{DoxyCode}
\hypertarget{md_sfcode_node_modules_minipass_README_autotoc_md17631}{}\doxysection{USAGE}\label{md_sfcode_node_modules_minipass_README_autotoc_md17631}
It\textquotesingle{}s a stream! Use it like a stream and it\textquotesingle{}ll most likely do what you want.


\begin{DoxyCode}{0}
\DoxyCodeLine{const Minipass = require('minipass')}
\DoxyCodeLine{const mp = new Minipass(options) // optional: \{ encoding, objectMode \}}
\DoxyCodeLine{mp.write('foo')}
\DoxyCodeLine{mp.pipe(someOtherStream)}
\DoxyCodeLine{mp.end('bar') }

\end{DoxyCode}
\hypertarget{md_sfcode_node_modules_minipass_README_autotoc_md17632}{}\doxysubsection{OPTIONS}\label{md_sfcode_node_modules_minipass_README_autotoc_md17632}

\begin{DoxyItemize}
\item {\ttfamily encoding} How would you like the data coming {\itshape out} of the stream to be encoded? Accepts any values that can be passed to {\ttfamily Buffer.\+to\+String()}.
\item {\ttfamily object\+Mode} Emit data exactly as it comes in. This will be flipped on by default if you write() something other than a string or Buffer at any point. Setting {\ttfamily object\+Mode\+: true} will prevent setting any encoding value.
\end{DoxyItemize}\hypertarget{md_sfcode_node_modules_minipass_README_autotoc_md17633}{}\doxysubsection{API}\label{md_sfcode_node_modules_minipass_README_autotoc_md17633}
Implements the user-\/facing portions of Node.\+js\textquotesingle{}s {\ttfamily Readable} and {\ttfamily Writable} streams.\hypertarget{md_sfcode_node_modules_minipass_README_autotoc_md17634}{}\doxysubsection{Methods}\label{md_sfcode_node_modules_minipass_README_autotoc_md17634}

\begin{DoxyItemize}
\item {\ttfamily write(chunk, \mbox{[}encoding\mbox{]}, \mbox{[}callback\mbox{]})} -\/ Put data in. (Note that, in the base Minipass class, the same data will come out.) Returns {\ttfamily false} if the stream will buffer the next write, or true if it\textquotesingle{}s still in \char`\"{}flowing\char`\"{} mode.
\item {\ttfamily end(\mbox{[}chunk, \mbox{[}encoding\mbox{]}\mbox{]}, \mbox{[}callback\mbox{]})} -\/ Signal that you have no more data to write. This will queue an {\ttfamily end} event to be fired when all the data has been consumed.
\item {\ttfamily set\+Encoding(encoding)} -\/ Set the encoding for data coming of the stream. This can only be done once.
\item {\ttfamily pause()} -\/ No more data for a while, please. This also prevents {\ttfamily end} from being emitted for empty streams until the stream is resumed.
\item {\ttfamily resume()} -\/ Resume the stream. If there\textquotesingle{}s data in the buffer, it is all discarded. Any buffered events are immediately emitted.
\item {\ttfamily pipe(dest)} -\/ Send all output to the stream provided. There is no way to unpipe. When data is emitted, it is immediately written to any and all pipe destinations.
\item {\ttfamily on(ev, fn)}, {\ttfamily emit(ev, fn)} -\/ Minipass streams are Event\+Emitters. Some events are given special treatment, however. (See below under \char`\"{}events\char`\"{}.)
\item {\ttfamily promise()} -\/ Returns a Promise that resolves when the stream emits {\ttfamily end}, or rejects if the stream emits {\ttfamily error}.
\item {\ttfamily collect()} -\/ Return a Promise that resolves on {\ttfamily end} with an array containing each chunk of data that was emitted, or rejects if the stream emits {\ttfamily error}. Note that this consumes the stream data.
\item {\ttfamily concat()} -\/ Same as {\ttfamily collect()}, but concatenates the data into a single Buffer object. Will reject the returned promise if the stream is in object\+Mode, or if it goes into object\+Mode by the end of the data.
\item {\ttfamily read(n)} -\/ Consume {\ttfamily n} bytes of data out of the buffer. If {\ttfamily n} is not provided, then consume all of it. If {\ttfamily n} bytes are not available, then it returns null. {\bfseries{Note}} consuming streams in this way is less efficient, and can lead to unnecessary Buffer copying.
\item {\ttfamily destroy(\mbox{[}er\mbox{]})} -\/ Destroy the stream. If an error is provided, then an `\textquotesingle{}error'{\ttfamily event is emitted. If the stream has a}close(){\ttfamily method, and has not emitted a}\textquotesingle{}close\textquotesingle{}{\ttfamily event yet, then}stream.\+close(){\ttfamily will be called. Any Promises returned by}.promise(){\ttfamily ,}.collect(){\ttfamily or }.concat()\`{} will be rejected. After being destroyed, writing to the stream will emit an error. No more data will be emitted if the stream is destroyed, even if it was previously buffered.
\end{DoxyItemize}\hypertarget{md_sfcode_node_modules_minipass_README_autotoc_md17635}{}\doxysubsection{Properties}\label{md_sfcode_node_modules_minipass_README_autotoc_md17635}

\begin{DoxyItemize}
\item {\ttfamily buffer\+Length} Read-\/only. Total number of bytes buffered, or in the case of object\+Mode, the total number of objects.
\item {\ttfamily encoding} The encoding that has been set. (Setting this is equivalent to calling {\ttfamily set\+Encoding(enc)} and has the same prohibition against setting multiple times.)
\item {\ttfamily flowing} Read-\/only. Boolean indicating whether a chunk written to the stream will be immediately emitted.
\item {\ttfamily emitted\+End} Read-\/only. Boolean indicating whether the end-\/ish events (ie, {\ttfamily end}, {\ttfamily prefinish}, {\ttfamily finish}) have been emitted. Note that listening on any end-\/ish event will immediateyl re-\/emit it if it has already been emitted.
\item {\ttfamily writable} Whether the stream is writable. Default {\ttfamily true}. Set to {\ttfamily false} when {\ttfamily end()}
\item {\ttfamily readable} Whether the stream is readable. Default {\ttfamily true}.
\item {\ttfamily buffer} A \href{http://npm.im/yallist}{\texttt{ yallist}} linked list of chunks written to the stream that have not yet been emitted. (It\textquotesingle{}s probably a bad idea to mess with this.)
\item {\ttfamily pipes} A \href{http://npm.im/yallist}{\texttt{ yallist}} linked list of streams that this stream is piping into. (It\textquotesingle{}s probably a bad idea to mess with this.)
\item {\ttfamily destroyed} A getter that indicates whether the stream was destroyed.
\item {\ttfamily paused} True if the stream has been explicitly paused, otherwise false.
\item {\ttfamily object\+Mode} Indicates whether the stream is in {\ttfamily object\+Mode}. Once set to {\ttfamily true}, it cannot be set to {\ttfamily false}.
\end{DoxyItemize}\hypertarget{md_sfcode_node_modules_minipass_README_autotoc_md17636}{}\doxysubsection{Events}\label{md_sfcode_node_modules_minipass_README_autotoc_md17636}

\begin{DoxyItemize}
\item {\ttfamily data} Emitted when there\textquotesingle{}s data to read. Argument is the data to read. This is never emitted while not flowing. If a listener is attached, that will resume the stream.
\item {\ttfamily end} Emitted when there\textquotesingle{}s no more data to read. This will be emitted immediately for empty streams when {\ttfamily end()} is called. If a listener is attached, and {\ttfamily end} was already emitted, then it will be emitted again. All listeners are removed when {\ttfamily end} is emitted.
\item {\ttfamily prefinish} An end-\/ish event that follows the same logic as {\ttfamily end} and is emitted in the same conditions where {\ttfamily end} is emitted. Emitted after `\textquotesingle{}end'{\ttfamily . $\ast$}finish{\ttfamily An end-\/ish event that follows the same logic as}end{\ttfamily and is emitted in the same conditions where}end{\ttfamily is emitted. Emitted after }\textquotesingle{}prefinish\textquotesingle{}{\ttfamily . $\ast$}close{\ttfamily An indication that an underlying resource has been released. Minipass does not emit this event, but will defer it until after}end\`{} has been emitted, since it throws off some stream libraries otherwise.
\item {\ttfamily drain} Emitted when the internal buffer empties, and it is again suitable to {\ttfamily write()} into the stream.
\item {\ttfamily readable} Emitted when data is buffered and ready to be read by a consumer.
\item {\ttfamily resume} Emitted when stream changes state from buffering to flowing mode. (Ie, when {\ttfamily resume} is called, {\ttfamily pipe} is called, or a {\ttfamily data} event listener is added.)
\end{DoxyItemize}\hypertarget{md_sfcode_node_modules_minipass_README_autotoc_md17637}{}\doxysubsection{Static Methods}\label{md_sfcode_node_modules_minipass_README_autotoc_md17637}

\begin{DoxyItemize}
\item {\ttfamily Minipass.\+is\+Stream(stream)} Returns {\ttfamily true} if the argument is a stream, and false otherwise. To be considered a stream, the object must be either an instance of Minipass, or an Event\+Emitter that has either a {\ttfamily pipe()} method, or both {\ttfamily write()} and {\ttfamily end()} methods. (Pretty much any stream in node-\/land will return {\ttfamily true} for this.)
\end{DoxyItemize}\hypertarget{md_sfcode_node_modules_minipass_README_autotoc_md17638}{}\doxysection{EXAMPLES}\label{md_sfcode_node_modules_minipass_README_autotoc_md17638}
Here are some examples of things you can do with Minipass streams.\hypertarget{md_sfcode_node_modules_minipass_README_autotoc_md17639}{}\doxysubsection{simple \char`\"{}are you done yet\char`\"{} promise}\label{md_sfcode_node_modules_minipass_README_autotoc_md17639}

\begin{DoxyCode}{0}
\DoxyCodeLine{mp.promise().then(() => \{}
\DoxyCodeLine{  // stream is finished}
\DoxyCodeLine{\}, er => \{}
\DoxyCodeLine{  // stream emitted an error}
\DoxyCodeLine{\}) }

\end{DoxyCode}
\hypertarget{md_sfcode_node_modules_minipass_README_autotoc_md17640}{}\doxysubsection{collecting}\label{md_sfcode_node_modules_minipass_README_autotoc_md17640}

\begin{DoxyCode}{0}
\DoxyCodeLine{mp.collect().then(all => \{}
\DoxyCodeLine{  // all is an array of all the data emitted}
\DoxyCodeLine{  // encoding is supported in this case, so}
\DoxyCodeLine{  // so the result will be a collection of strings if}
\DoxyCodeLine{  // an encoding is specified, or buffers/objects if not.}
\DoxyCodeLine{  //}
\DoxyCodeLine{  // In an async function, you may do}
\DoxyCodeLine{  // const data = await stream.collect()}
\DoxyCodeLine{\}) }

\end{DoxyCode}
\hypertarget{md_sfcode_node_modules_minipass_README_autotoc_md17641}{}\doxysubsection{collecting into a single blob}\label{md_sfcode_node_modules_minipass_README_autotoc_md17641}
This is a bit slower because it concatenates the data into one chunk for you, but if you\textquotesingle{}re going to do it yourself anyway, it\textquotesingle{}s convenient this way\+:


\begin{DoxyCode}{0}
\DoxyCodeLine{mp.concat().then(onebigchunk => \{}
\DoxyCodeLine{  // onebigchunk is a string if the stream}
\DoxyCodeLine{  // had an encoding set, or a buffer otherwise.}
\DoxyCodeLine{\}) }

\end{DoxyCode}
\hypertarget{md_sfcode_node_modules_minipass_README_autotoc_md17642}{}\doxysubsection{iteration}\label{md_sfcode_node_modules_minipass_README_autotoc_md17642}
You can iterate over streams synchronously or asynchronously in platforms that support it.

Synchronous iteration will end when the currently available data is consumed, even if the {\ttfamily end} event has not been reached. In string and buffer mode, the data is concatenated, so unless multiple writes are occurring in the same tick as the {\ttfamily read()}, sync iteration loops will generally only have a single iteration.

To consume chunks in this way exactly as they have been written, with no flattening, create the stream with the {\ttfamily \{ object\+Mode\+: true \}} option.


\begin{DoxyCode}{0}
\DoxyCodeLine{const mp = new Minipass(\{ objectMode: true \})}
\DoxyCodeLine{mp.write('a')}
\DoxyCodeLine{mp.write('b')}
\DoxyCodeLine{for (let letter of mp) \{}
\DoxyCodeLine{  console.log(letter) // a, b}
\DoxyCodeLine{\}}
\DoxyCodeLine{mp.write('c')}
\DoxyCodeLine{mp.write('d')}
\DoxyCodeLine{for (let letter of mp) \{}
\DoxyCodeLine{  console.log(letter) // c, d}
\DoxyCodeLine{\}}
\DoxyCodeLine{mp.write('e')}
\DoxyCodeLine{mp.end()}
\DoxyCodeLine{for (let letter of mp) \{}
\DoxyCodeLine{  console.log(letter) // e}
\DoxyCodeLine{\}}
\DoxyCodeLine{for (let letter of mp) \{}
\DoxyCodeLine{  console.log(letter) // nothing}
\DoxyCodeLine{\} }

\end{DoxyCode}


Asynchronous iteration will continue until the end event is reached, consuming all of the data.


\begin{DoxyCode}{0}
\DoxyCodeLine{const mp = new Minipass(\{ encoding: 'utf8' \})}
\DoxyCodeLine{}
\DoxyCodeLine{// some source of some data}
\DoxyCodeLine{let i = 5}
\DoxyCodeLine{const inter = setInterval(() => \{}
\DoxyCodeLine{  if (i -\/-\/> 0)}
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\hypertarget{md_sfcode_node_modules_minipass_README_autotoc_md17643}{}\doxysubsection{subclass that $<$tt$>$console.\+log()$<$/tt$>$s everything written into it}\label{md_sfcode_node_modules_minipass_README_autotoc_md17643}

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\DoxyCodeLine{class Logger extends Minipass \{}
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\hypertarget{md_sfcode_node_modules_minipass_README_autotoc_md17644}{}\doxysubsection{same thing, but using an inline anonymous class}\label{md_sfcode_node_modules_minipass_README_autotoc_md17644}

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\hypertarget{md_sfcode_node_modules_minipass_README_autotoc_md17645}{}\doxysubsection{subclass that defers \textquotesingle{}end\textquotesingle{} for some reason}\label{md_sfcode_node_modules_minipass_README_autotoc_md17645}

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\DoxyCodeLine{  \}}
\DoxyCodeLine{\} }

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\hypertarget{md_sfcode_node_modules_minipass_README_autotoc_md17646}{}\doxysubsection{transform that creates newline-\/delimited JSON}\label{md_sfcode_node_modules_minipass_README_autotoc_md17646}

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\DoxyCodeLine{class NDJSONEncode extends Minipass \{}
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\DoxyCodeLine{  end (obj, cb) \{}
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\hypertarget{md_sfcode_node_modules_minipass_README_autotoc_md17647}{}\doxysubsection{transform that parses newline-\/delimited JSON}\label{md_sfcode_node_modules_minipass_README_autotoc_md17647}

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