dominictarr/level-fix-range — pull request #2 by juliangruber (2013-07-25 15:06:16+00:00)
Title: don't cause side effects

before this fix, if you were to reuse the options object, like

```js
var opts = { start: 'a' , end: 'b' }
db.createReadStream(opts)

opts.reverse = true
db.createReadStream(fix(opts))
```

things could possibly go wrong