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'use strict';
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require('../common');
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var Readable = require('stream').Readable;
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var assert = require('assert');
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var s = new Readable({
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highWaterMark: 20,
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encoding: 'ascii'
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});
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var list = ['1', '2', '3', '4', '5', '6'];
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s._read = function(n) {
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var one = list.shift();
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stream: There is no _read cb, there is only push
This makes it so that `stream.push(chunk)` is the only way to signal the
end of reading, removing the confusing disparity between the
callback-style _read method, and the fact that most real-world streams
do not have a 1:1 corollation between the "please give me data" event,
and the actual arrival of a chunk of data.
It is still possible, of course, to implement a `CallbackReadable` on
top of this. Simply provide a method like this as the callback:
function readCallback(er, chunk) {
if (er)
stream.emit('error', er);
else
stream.push(chunk);
}
However, *only* fs streams actually would behave in this way, so it
makes not a lot of sense to make TCP, TLS, HTTP, and all the rest have
to bend into this uncomfortable paradigm.
12 years ago
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if (!one) {
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s.push(null);
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} else {
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var two = list.shift();
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s.push(one);
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s.push(two);
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}
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};
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s.read(0);
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// ACTUALLY [1, 3, 5, 6, 4, 2]
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process.on('exit', function() {
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assert.deepStrictEqual(s._readableState.buffer,
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['1', '2', '3', '4', '5', '6']);
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console.log('ok');
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});
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