Feature: Support empty statement in new planner

[leiysky]

Accept /* foo bar */ ; as Statement::Empty and then do nothing in execution.

[andylokandy]

Does the Empty Statement the same as the normal statement?

[leiysky]

Does the Empty Statement the same as the normal statement?

Which part do you mean? IMO there is no difference between them, EmptyStatement is just another variant of Statement, and will be processed by Binder, Interpreter(i.e. EmptyInterpreter) as well.