How to send data to the client.
Most often, this is
Send, but when a push promise is created,
this will be
Push. This can be used by
Send(&'a mut ResponsePipe)
Send the response normally.
Push(&'a mut PushedResponsePipe)
Send the response as a HTTP/2 push.
Ensures correct version and length (only applicable for HTTP/1 connections) of a response according to inner enum variants.
response to this pipe.
returns any errors with sending the data.
Returns the argument unchanged.