FILTER_GEN_TAC : (term -> tactic)

- STRUCTURE
- SYNOPSIS
- Strips off a universal quantifier, but fails for a given quantified variable.
- DESCRIPTION
- When applied to a term s and a goal A ?- !x. t, the tactic FILTER_GEN_TAC fails if the quantified variable x is the same as s, but otherwise advances the goal in the same way as GEN_TAC, i.e. returns the goal A ?- t[x'/x] where x' is a variant of x chosen to avoid clashing with any variables free in the goal’s assumption list. Normally x' is just x.
A ?- !x. t ============== FILTER_GEN_TAC "s" A ?- t[x'/x]

- FAILURE
- Fails if the goal’s conclusion is not universally quantified or the quantified variable is equal to the given term.
- SEEALSO

HOL Kananaskis-14