FIRST_TCL : (thm_tactical list -> thm_tactical)

SYNOPSIS
Applies the first theorem-tactical in a list which succeeds.

DESCRIBE
When applied to a list of theorem-tacticals, a theorem-tactic and a theorem, FIRST_TCL returns the tactic resulting from the application of the first theorem-tactical to the theorem-tactic and theorem which succeeds. The effect is the same as:
   FIRST_TCL [ttl1;...;ttln] = ttl1 ORELSE_TCL ... ORELSE_TCL ttln

FAILURE
FIRST_TCL fails iff each tactic in the list fails when applied to the theorem-tactic and theorem. This is trivially the case if the list is empty.

SEEALSO  EVERY_TCL,   ORELSE_TCL,   REPEAT_TCL,   THEN_TCL

HOL  Kananaskis 0