EQF_INTRO
Drule.EQF_INTRO : (thm -> thm)
Converts negation to equality with F.
F
A |- ~tm ------------- EQF_INTRO A |- tm = F
Fails if the argument theorem is not a negation.
Drule.EQF_ELIM, Drule.EQT_ELIM, Drule.EQT_INTRO
Drule.EQF_ELIM
Drule.EQT_ELIM
Drule.EQT_INTRO