79 lines
1.4 KiB
Markdown
79 lines
1.4 KiB
Markdown
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# fast-fifo
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A fast fifo implementation similar to the one powering nextTick in Node.js core
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```
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npm install fast-fifo
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```
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Uses a linked list of growing fixed sized arrays to implement the FIFO to avoid
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allocating a wrapper object for each item.
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## Usage
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``` js
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const FIFO = require('fast-fifo')
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const q = new FIFO()
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q.push('hello')
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q.push('world')
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q.shift() // returns hello
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q.shift() // returns world
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```
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## API
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#### `q = new FIFO()`
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Create a new FIFO.
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#### `q.push(value)`
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Push a value to the FIFO. `value` can be anything other than undefined.
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#### `value = q.shift()`
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Return the oldest value from the FIFO.
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#### `q.clear()`
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Remove all values from the FIFO.
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#### `bool = q.isEmpty()`
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Returns `true` if the FIFO is empty and false otherwise.
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#### `value = q.peek()`
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Return the oldest value from the FIFO without shifting it out.
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#### `len = q.length`
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Get the number of entries remaining in the FIFO.
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## Benchmarks
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Included in bench.js is a simple benchmark that benchmarks this against a simple
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linked list based FIFO.
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On my machine the benchmark looks like this:
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```
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fifo bulk push and shift: 2881.508ms
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fifo individual push and shift: 3248.437ms
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fast-fifo bulk push and shift: 1606.972ms
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fast-fifo individual push and shift: 1328.064ms
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fifo bulk push and shift: 3266.902ms
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fifo individual push and shift: 3320.944ms
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fast-fifo bulk push and shift: 1858.307ms
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fast-fifo individual push and shift: 1516.983ms
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```
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YMMV
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## License
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MIT
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