# Notes

(new notes at the top)

## TODO: Incremental Watcher

The DAG based incremental rebuilding will require a better file watcher that can whats entire directories and automatically recheck build rules when a new file is created.

```go
type WatchListener func(path string) error

type Watcher interface {
    // OnFileChange will register a file change listener
    OnFileChange(l WatchListener)

    // OnFileAdded will register a file creation listener
    OnFileAdded(l WatchListener)

    // Watch will register "path"
    Watch(path string) error

    // Watch will register files matching "pattern" and all directories along the way for new files
    WatchPattern(pattern string) error
}
```