OR_CONV : conv
OR_CONV "T \/ t" = |- T \/ t = T OR_CONV "t \/ T" = |- t \/ T = T OR_CONV "F \/ t" = |- F \/ t = t OR_CONV "t \/ F" = |- t \/ F = t OR_CONV "t \/ t" = |- t \/ t = t
#OR_CONV "F \/ T";; |- F \/ T = T #OR_CONV "X \/ F";; |- X \/ F = X #OR_CONV "(!n. n + 1 = SUC n) \/ (!m. m + 1 = SUC m)";; |- (!n. n + 1 = SUC n) \/ (!m. m + 1 = SUC m) = (!n. n + 1 = SUC n)