My concern is that resource parameters aren't guaranteed to be boolean values. `resource[:multiple]` could also be `true:TrueClass`, `true:Symbol`, or `true:String`, depending on the manifest syntax. Here are the main cases I'm worried about:

```puppet
file_line { 'foo':
  multiple => true, # should be a symbol
}

file_line { 'bar':
  multiple => 'true' # should be a string
}
```

Could you check if this sort of manifest would work as expected?