NTH_GOAL : tactic -> int -> list_tactic

- STRUCTURE
- SYNOPSIS
- The list-tactic which applies a tactic to the n’th member of a list of goals.
- DESCRIPTION
- If tac is a tactic, NTH_GOAL n tac is a list-tactic which applies the tactic tac to the n’th member of a list of goals.
Note that in the interactive system, subgoals are printed in reverse order of their numbering.

- FAILURE
- The application of NTH_GOAL to a tactic and integer never fails. The resulting list-tactic fails if n is less than 1 or greater than the length of the goal list, or finally if tac fails when applied to the n’th member of the goal list.
- USES
- Applying a tactic to a particular subgoal.
- EXAMPLE
- Where tac1 and tac2 are tactics, tac1 THEN_LT NTH_GOAL n tac2 applies tac1 to a goal, and then applies tac2 to the n’th resulting subgoal.
- SEEALSO

HOL Kananaskis-13