69 lines
1.5 KiB
Markdown
69 lines
1.5 KiB
Markdown
# block-stream2
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transform input into equally-sized chunks as output
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streams3 version of
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[block-stream](https://npmjs.org/package/block-stream)
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[](http://travis-ci.org/substack/block-stream2)
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# example
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``` js
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const BlockStream = require('block-stream2');
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const through = require('through2');
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process.stdin
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.pipe(new BlockStream({ size: 16, zeroPadding: true }))
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.pipe(through((buf, enc, next) => {
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const str = buf.toString().replace(/[\x00-\x1f]/g, chr);
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console.log(`buf[${buf.length}]=${str}`);
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next();
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}))
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;
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function chr (s) { return `\\x${pad(s.charCodeAt(0).toString(16),2)}` }
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function pad (s, n) { return Array(n - s.length + 1).join('0') + s }
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```
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```
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$ echo {c,d,f}{a,e,i,o,u}{t,g,r} | node example/stream.js
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buf[16]=cat cag car cet
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buf[16]=ceg cer cit cig
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buf[16]=cir cot cog cor
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buf[16]=cut cug cur dat
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buf[16]=dag dar det deg
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buf[16]=der dit dig dir
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buf[16]=dot dog dor dut
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buf[16]=dug dur fat fag
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buf[16]=far fet feg fer
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buf[16]=fit fig fir fot
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buf[16]=fog for fut fug
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buf[16]=fur\x0a\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00
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```
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# methods
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``` js
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const BlockStream = require('block-stream2');
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```
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## const b = new BlockStream(opts)
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## const b = new BlockStream(size, opts)
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Create a new transform stream `b` that outputs chunks of length `size` or
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`opts.size`.
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When `opts.zeroPadding` is false, do not zero-pad the last chunk.
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# install
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With [npm](https://npmjs.org) do:
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```
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npm install block-stream2
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```
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# license
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MIT
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