Synchronously applies all registered handlers for `name`. The handler functions are called with the return value of the previous handler and all args. For the first handler `init` is used and the return value of the last handler is return by `applyPluginsWaterfall`
Asynchronously applies all registered handlers for `name`. The handler functions are called with all args and a callback function with the signature `(err?: Error) -> void`. The handler functions are called in order of registration.
Synchronously applies all registered handlers for `name`. The handler function are called with all args. If a handler function returns something `!== undefined`, the value is returned and no more handlers are applied.
Asynchronously applies all registered handlers for `name`. The handler functions are called with the current value and a callback function with the signature `(err: Error, nextValue: any) -> void`. When called, `nextValue` is the current value for the next handler. The current value for the first handler is `init`. After all handlers are applied, `callback` is called with the last value. If any handler passes a value for `err`, the `callback` is called with this error and no more handlers are called.
Asynchronously applies all registered handlers for `name`. The handler functions are called with all `args` and a callback function with the signature `(err: Error) -> void`. The handlers are called in series, one at a time. After all handlers are applied, `callback` is called. If any handler passes a value for `err`, the `callback` is called with this error and no more handlers are called.
Applies all registered handlers for `name` in parallel. The handler functions are called with all args and a callback function with the signature `(err?: Error) -> void`. The `callback` function is called when all handlers have called the callback without `err`. If any handler calls the callback with `err`, `callback` is invoked with this error and the other handlers are ignored.
Applies all registered handlers for `name` in parallel. The handler functions are called with all args and a callback function with the signature `(err?: Error) -> void`. Handler functions must call the callback. They can either pass an error, pass undefined, or pass a value. The first result (either error or value) which is not undefined is passed to the `callback`. The order is defined by registration, not by the speed of the handler function.
### hasPlugins
``` js
hasPlugins(
name: string
)
```
Returns true, if plugins are registered for this name.