Basic directives are building blocks for building Custom Directives. As such they usually aren’t used in a route directly but rather in the definition of new directives.
Directives to provide values to inner routes
These directives allow to provide the inner routes with extractions. They can be distinguished
on two axes: a) provide a constant value or extract a value from the
RequestContext b) provide
a single value or an HList of values.
Directives transforming the response
These directives allow to hook into the response path and transform the complete response or the parts of a response or the list of rejections:
Directives hooking into the responder chain
These directives allow to hook into The Responder Chain. The first two allow transforming the response message to a new message. The latter one allows to completely replace the response message with the execution of a new route.