A requires port can be specified to be injected:
requires injected ilogger l;
This indicates that the port can be bound to a corresponding port
residing at any level in the system hierarchy. An injected port
is the exception to the one to one rule, i.e., it allows many ports to
be connected to a single instance. For this reason out events
are not allowed in interfaces which are injected.
See Systems for a detailed description of the binding of injected ports.