@startuml
!include sequence_header.iuml

skinparam participantPadding 50

participant Caller
participant Target

Caller ->(10) Target : next(long)
Target ->(10) Caller : value
Target ->(10) Caller : value
Target ->(10) Caller : value
...

alt
Target ->(10) Caller : value
else
Target -->(10) Caller : error
else
Target -->(10) Caller : no value
end

@enduml
