adam@0: val init : transaction {}
adam@2: 
adam@2: type discovery
adam@2: val discover : string -> transaction (option discovery)
adam@2: val endpoint : discovery -> string
adam@2: val localId : discovery -> option string
adam@3: 
adam@3: type inputs
adam@3: val createInputs : transaction inputs
adam@3: val addInput : inputs -> string -> string -> transaction {}
adam@3: 
adam@3: type outputs
adam@3: val getOutput : outputs -> string -> option string
adam@3: 
adam@3: val indirect : string -> inputs -> transaction outputs