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# memory-pager
Access memory using small fixed sized buffers instead of allocating a huge buffer.
Useful if you are implementing sparse data structures (such as large bitfield).
![travis](https://travis-ci.org/mafintosh/memory-pager.svg?branch=master)
```
npm install memory-pager
```
## Usage
``` js
var pager = require('paged-memory')
var pages = pager(1024) // use 1kb per page
var page = pages.get(10) // get page #10
console.log(page.offset) // 10240
console.log(page.buffer) // a blank 1kb buffer
```
## API
#### `var pages = pager(pageSize)`
Create a new pager. `pageSize` defaults to `1024`.
#### `var page = pages.get(pageNumber, [noAllocate])`
Get a page. The page will be allocated at first access.
Optionally you can set the `noAllocate` flag which will make the
method return undefined if no page has been allocated already
A page looks like this
``` js
{
offset: byteOffset,
buffer: bufferWithPageSize
}
```
#### `pages.set(pageNumber, buffer)`
Explicitly set the buffer for a page.
#### `pages.updated(page)`
Mark a page as updated.
#### `pages.lastUpdate()`
Get the last page that was updated.
#### `var buf = pages.toBuffer()`
Concat all pages allocated pages into a single buffer
## License
MIT