Returns result of first tactical, if there is any, else it returns the result of the second tactical, with the possibility of no result from either.
Returns result of first tactical, if there is any, else it returns the result of the second tactical, with the possibility of no result from either.
The Tactical to be repeated.
Applies the given Tactical to the proof state until it fails.
Note that the tactical is not required to succeed at least once, i.e. it might fail immediately.
The Tactical to be repeated.