def negate_clause(c: Expr) -> Expr:
if isinstance(c, syntax.Bool):
return syntax.Bool(not c.val)
elif isinstance(c, syntax.UnaryExpr):
assert c.op == 'NOT'
return c.arg
elif isinstance(c, syntax.BinaryExpr):
assert c.op in ['EQUAL', 'NOTEQ']
op = 'NOTEQ' if c.op == 'EQUAL' else 'EQUAL'
return syntax.BinaryExpr(op, c.arg1, c.arg2)
elif isinstance(c, syntax.NaryExpr):
assert c.op == 'OR'
return syntax.NaryExpr('AND', [negate_clause(arg) for arg in c.args])
elif isinstance(c, syntax.AppExpr) or isinstance(c, syntax.Id):
return syntax.Not(c)
else:
assert False, f'unsupported expression {c} in negate_clause'
def negate_clause(c: Expr) -> Expr:
if isinstance(c, syntax.Bool):
return syntax.Bool(not c.val)
elif isinstance(c, syntax.UnaryExpr):
assert c.op == 'NOT'
return c.arg
elif isinstance(c, syntax.BinaryExpr):
assert c.op in ['EQUAL', 'NOTEQ']
op = 'NOTEQ' if c.op == 'EQUAL' else 'EQUAL'
return syntax.BinaryExpr(op, c.arg1, c.arg2)
elif isinstance(c, syntax.NaryExpr):
assert c.op == 'OR'
return syntax.NaryExpr('AND', tuple(negate_clause(arg) for arg in c.args))
elif isinstance(c, syntax.AppExpr) or isinstance(c, syntax.Id):
return syntax.Not(c)
elif isinstance(c, syntax.QuantifierExpr):
assert c.quant == 'FORALL'
return syntax.QuantifierExpr('EXISTS', c.get_vs(), negate_clause(c.body))
else:
assert False, f'unsupported expression {c} in negate_clause'
def p_expr_false(p: Any) -> None:
'expr : FALSE'
p[0] = syntax.Bool(p.slice[1], False)
def p_expr_true(p: Any) -> None:
'expr : TRUE'
p[0] = syntax.Bool(p.slice[1], True)
def p_expr_false(p: Any) -> None:
'expr : FALSE'
p[0] = syntax.Bool(False, span=span_from_tok(p.slice[1]))
def p_expr_true(p: Any) -> None:
'expr : TRUE'
p[0] = syntax.Bool(True, span=span_from_tok(p.slice[1]))