def __init__(self, *operands):
'''
Or together any number of operands: A or B or C
'''
Operation.__init__(self, Or._operator_, operands)
# deduce trivial disjunctive equivalances with 0 or 1 operand
# avoid infinite recursion by storing previously encountered
# expressions
if self in Or.trivial_disjunctions:
return
operands = self.operands
if operands.num_entries() == 0:
Or.trivial_disjunctions.add(self)
try:
from proveit.logic.booleans.disjunction import empty_disjunction
except BaseException:
pass # empty_disjunction not initially defined when doing a clean rebuild
if operands.is_single():
operand = operands[0]
try:
Or.trivial_disjunctions.add(self)
in_bool(operand).prove(automation=False)
self.unary_reduction()
except BaseException:
pass
def derive_in_bool(self, assumptions=USE_DEFAULTS):
'''
From (A and B and ... and Z) derive [(A and B and ... and Z) in Boolean].
'''
return in_bool(self).prove(assumptions=assumptions)
def derive_in_bool(self, assumptions=USE_DEFAULTS):
'''
From Not(A) derive [Not(A) in Boolean].
'''
return in_bool(self).prove(assumptions=assumptions)