OptionaldataData is arbitrary runtime-dependent data.
OptionalfeeFee is the fee sent into the runtime as part of the message being sent. The fee is transferred before the message is processed by the runtime.
ID is the destination runtime ID.
OptionaltagTag is an optional tag provided by the caller which is ignored and can be used to match processed incoming message events later.
OptionaltokensTokens are any tokens sent into the runtime as part of the message being sent. The tokens are transferred before the message is processed by the runtime.
SubmitMsg is the argument set for the SubmitMsg method.