Goal Class Reference

Inheritance diagram for Goal:

Public Member Functions
def	__init__
def	__del__ (self)
def	depth (self)
def	inconsistent (self)
def	prec (self)
def	precision (self)
def	size (self)
def	__len__ (self)
def	get (self, i)
def	__getitem__ (self, arg)
def	assert_exprs (self, args)
def	append (self, args)
def	insert (self, args)
def	add (self, args)
def	convert_model (self, model)
def	__repr__ (self)
def	sexpr (self)
def	dimacs
def	translate (self, target)
def	__copy__ (self)
def	__deepcopy__
def	simplify (self, arguments, keywords)
def	as_expr (self)
Public Member Functions inherited from Z3PPObject
def	use_pp (self)

Data Fields
	ctx
	goal

Detailed Description

Goal is a collection of constraints we want to find a solution or show to be unsatisfiable (infeasible).

Goals are processed using Tactics. A Tactic transforms a goal into a set of subgoals.
A goal has a solution if one of its subgoals has a solution.
A goal is unsatisfiable if all subgoals are unsatisfiable.

Definition at line 5637 of file z3py.py.

Constructor & Destructor Documentation

def __init__	(		self,
			models = True,
			unsat_cores = False,
			proofs = False,
			ctx = None,
			goal = None
	)

Definition at line 5645 of file z3py.py.

    def __init__(self, models=True, unsat_cores=False, proofs=False, ctx=None, goal=None):
        if z3_debug():
            _z3_assert(goal is None or ctx is not None,
                       "If goal is different from None, then ctx must be also different from None")
        self.ctx = _get_ctx(ctx)
        self.goal = goal
        if self.goal is None:
            self.goal = Z3_mk_goal(self.ctx.ref(), models, unsat_cores, proofs)
        Z3_goal_inc_ref(self.ctx.ref(), self.goal)

def __del__

(

self

)

Definition at line 5655 of file z3py.py.

    def __del__(self):
        if self.goal is not None and self.ctx.ref() is not None and Z3_goal_dec_ref is not None:
            Z3_goal_dec_ref(self.ctx.ref(), self.goal)

Member Function Documentation

def __copy__

(

self

)

Definition at line 5890 of file z3py.py.

    def __copy__(self):
        return self.translate(self.ctx)

def __deepcopy__	(		self,
			memo = {}
	)

Definition at line 5893 of file z3py.py.

    def __deepcopy__(self, memo={}):
        return self.translate(self.ctx)

def __getitem__	(		self,
			arg
	)

Return a constraint in the goal `self`.

>>> g = Goal()
>>> x, y = Ints('x y')
>>> g.add(x == 0, y > x)
>>> g[0]
x == 0
>>> g[1]
y > x

Definition at line 5764 of file z3py.py.

    def __getitem__(self, arg):
        """Return a constraint in the goal `self`.

        >>> g = Goal()
        >>> x, y = Ints('x y')
        >>> g.add(x == 0, y > x)
        >>> g[0]
        x == 0
        >>> g[1]
        y > x
        """
        if arg >= len(self):
            raise IndexError
        return self.get(arg)

def __len__

(

self

)

Return the number of constraints in the goal `self`.

>>> g = Goal()
>>> len(g)
0
>>> x, y = Ints('x y')
>>> g.add(x == 0, y > x)
>>> len(g)
2

Definition at line 5738 of file z3py.py.

Referenced by AstVector.__getitem__(), and AstVector.__setitem__().

    def __len__(self):
        """Return the number of constraints in the goal `self`.

        >>> g = Goal()
        >>> len(g)
        0
        >>> x, y = Ints('x y')
        >>> g.add(x == 0, y > x)
        >>> len(g)
        2
        """
        return self.size()

def __repr__

(

self

)

Definition at line 5856 of file z3py.py.

    def __repr__(self):
        return obj_to_string(self)

def add	(		self,
			args
	)

Add constraints.

>>> x = Int('x')
>>> g = Goal()
>>> g.add(x > 0, x < 2)
>>> g
[x > 0, x < 2]

Definition at line 5816 of file z3py.py.

Referenced by Fixedpoint.__iadd__(), and Optimize.__iadd__().

    def add(self, *args):
        """Add constraints.

        >>> x = Int('x')
        >>> g = Goal()
        >>> g.add(x > 0, x < 2)
        >>> g
        [x > 0, x < 2]
        """
        self.assert_exprs(*args)

def append	(		self,
			args
	)

Add constraints.

>>> x = Int('x')
>>> g = Goal()
>>> g.append(x > 0, x < 2)
>>> g
[x > 0, x < 2]

Definition at line 5794 of file z3py.py.

    def append(self, *args):
        """Add constraints.

        >>> x = Int('x')
        >>> g = Goal()
        >>> g.append(x > 0, x < 2)
        >>> g
        [x > 0, x < 2]
        """
        self.assert_exprs(*args)

def as_expr

(

self

)

Return goal `self` as a single Z3 expression.

>>> x = Int('x')
>>> g = Goal()
>>> g.as_expr()
True
>>> g.add(x > 1)
>>> g.as_expr()
x > 1
>>> g.add(x < 10)
>>> g.as_expr()
And(x > 1, x < 10)

Definition at line 5916 of file z3py.py.

    def as_expr(self):
        """Return goal `self` as a single Z3 expression.

        >>> x = Int('x')
        >>> g = Goal()
        >>> g.as_expr()
        True
        >>> g.add(x > 1)
        >>> g.as_expr()
        x > 1
        >>> g.add(x < 10)
        >>> g.as_expr()
        And(x > 1, x < 10)
        """
        sz = len(self)
        if sz == 0:
            return BoolVal(True, self.ctx)
        elif sz == 1:
            return self.get(0)
        else:
            return And([self.get(i) for i in range(len(self))], self.ctx)

def assert_exprs	(		self,
			args
	)

Assert constraints into the goal.

>>> x = Int('x')
>>> g = Goal()
>>> g.assert_exprs(x > 0, x < 2)
>>> g
[x > 0, x < 2]

Definition at line 5779 of file z3py.py.

Referenced by Goal.add(), Fixedpoint.add(), Optimize.add(), Goal.append(), Fixedpoint.append(), and Fixedpoint.insert().

    def assert_exprs(self, *args):
        """Assert constraints into the goal.

        >>> x = Int('x')
        >>> g = Goal()
        >>> g.assert_exprs(x > 0, x < 2)
        >>> g
        [x > 0, x < 2]
        """
        args = _get_args(args)
        s = BoolSort(self.ctx)
        for arg in args:
            arg = s.cast(arg)
            Z3_goal_assert(self.ctx.ref(), self.goal, arg.as_ast())

def convert_model	(		self,
			model
	)

Retrieve model from a satisfiable goal
>>> a, b = Ints('a b')
>>> g = Goal()
>>> g.add(Or(a == 0, a == 1), Or(b == 0, b == 1), a > b)
>>> t = Then(Tactic('split-clause'), Tactic('solve-eqs'))
>>> r = t(g)
>>> r[0]
[Or(b == 0, b == 1), Not(0 <= b)]
>>> r[1]
[Or(b == 0, b == 1), Not(1 <= b)]
>>> # Remark: the subgoal r[0] is unsatisfiable
>>> # Creating a solver for solving the second subgoal
>>> s = Solver()
>>> s.add(r[1])
>>> s.check()
sat
>>> s.model()
[b = 0]
>>> # Model s.model() does not assign a value to `a`
>>> # It is a model for subgoal `r[1]`, but not for goal `g`
>>> # The method convert_model creates a model for `g` from a model for `r[1]`.
>>> r[1].convert_model(s.model())
[b = 0, a = 1]

Definition at line 5827 of file z3py.py.

    def convert_model(self, model):
        """Retrieve model from a satisfiable goal
        >>> a, b = Ints('a b')
        >>> g = Goal()
        >>> g.add(Or(a == 0, a == 1), Or(b == 0, b == 1), a > b)
        >>> t = Then(Tactic('split-clause'), Tactic('solve-eqs'))
        >>> r = t(g)
        >>> r[0]
        [Or(b == 0, b == 1), Not(0 <= b)]
        >>> r[1]
        [Or(b == 0, b == 1), Not(1 <= b)]
        >>> # Remark: the subgoal r[0] is unsatisfiable
        >>> # Creating a solver for solving the second subgoal
        >>> s = Solver()
        >>> s.add(r[1])
        >>> s.check()
        sat
        >>> s.model()
        [b = 0]
        >>> # Model s.model() does not assign a value to `a`
        >>> # It is a model for subgoal `r[1]`, but not for goal `g`
        >>> # The method convert_model creates a model for `g` from a model for `r[1]`.
        >>> r[1].convert_model(s.model())
        [b = 0, a = 1]
        """
        if z3_debug():
            _z3_assert(isinstance(model, ModelRef), "Z3 Model expected")
        return ModelRef(Z3_goal_convert_model(self.ctx.ref(), self.goal, model.model), self.ctx)

def depth

(

self

)

Return the depth of the goal `self`.
The depth corresponds to the number of tactics applied to `self`.

>>> x, y = Ints('x y')
>>> g = Goal()
>>> g.add(x == 0, y >= x + 1)
>>> g.depth()
0
>>> r = Then('simplify', 'solve-eqs')(g)
>>> # r has 1 subgoal
>>> len(r)
1
>>> r[0].depth()
2

Definition at line 5659 of file z3py.py.

    def depth(self):
        """Return the depth of the goal `self`.
        The depth corresponds to the number of tactics applied to `self`.

        >>> x, y = Ints('x y')
        >>> g = Goal()
        >>> g.add(x == 0, y >= x + 1)
        >>> g.depth()
        0
        >>> r = Then('simplify', 'solve-eqs')(g)
        >>> # r has 1 subgoal
        >>> len(r)
        1
        >>> r[0].depth()
        2
        """
        return int(Z3_goal_depth(self.ctx.ref(), self.goal))

def dimacs	(		self,
			include_names = True
	)

Return a textual representation of the goal in DIMACS format.

Definition at line 5863 of file z3py.py.

    def dimacs(self, include_names=True):
        """Return a textual representation of the goal in DIMACS format."""
        return Z3_goal_to_dimacs_string(self.ctx.ref(), self.goal, include_names)

def get	(		self,
			i
	)

Return a constraint in the goal `self`.

>>> g = Goal()
>>> x, y = Ints('x y')
>>> g.add(x == 0, y > x)
>>> g.get(0)
x == 0
>>> g.get(1)
y > x

Definition at line 5751 of file z3py.py.

Referenced by Goal.__getitem__(), and Goal.as_expr().

    def get(self, i):
        """Return a constraint in the goal `self`.

        >>> g = Goal()
        >>> x, y = Ints('x y')
        >>> g.add(x == 0, y > x)
        >>> g.get(0)
        x == 0
        >>> g.get(1)
        y > x
        """
        return _to_expr_ref(Z3_goal_formula(self.ctx.ref(), self.goal, i), self.ctx)

def inconsistent

(

self

)

Return `True` if `self` contains the `False` constraints.

>>> x, y = Ints('x y')
>>> g = Goal()
>>> g.inconsistent()
False
>>> g.add(x == 0, x == 1)
>>> g
[x == 0, x == 1]
>>> g.inconsistent()
False
>>> g2 = Tactic('propagate-values')(g)[0]
>>> g2.inconsistent()
True

Definition at line 5677 of file z3py.py.

    def inconsistent(self):
        """Return `True` if `self` contains the `False` constraints.

        >>> x, y = Ints('x y')
        >>> g = Goal()
        >>> g.inconsistent()
        False
        >>> g.add(x == 0, x == 1)
        >>> g
        [x == 0, x == 1]
        >>> g.inconsistent()
        False
        >>> g2 = Tactic('propagate-values')(g)[0]
        >>> g2.inconsistent()
        True
        """
        return Z3_goal_inconsistent(self.ctx.ref(), self.goal)

def insert	(		self,
			args
	)

Add constraints.

>>> x = Int('x')
>>> g = Goal()
>>> g.insert(x > 0, x < 2)
>>> g
[x > 0, x < 2]

Definition at line 5805 of file z3py.py.

    def insert(self, *args):
        """Add constraints.

        >>> x = Int('x')
        >>> g = Goal()
        >>> g.insert(x > 0, x < 2)
        >>> g
        [x > 0, x < 2]
        """
        self.assert_exprs(*args)

def prec

(

self

)

Return the precision (under-approximation, over-approximation, or precise) of the goal `self`.

>>> g = Goal()
>>> g.prec() == Z3_GOAL_PRECISE
True
>>> x, y = Ints('x y')
>>> g.add(x == y + 1)
>>> g.prec() == Z3_GOAL_PRECISE
True
>>> t  = With(Tactic('add-bounds'), add_bound_lower=0, add_bound_upper=10)
>>> g2 = t(g)[0]
>>> g2
[x == y + 1, x <= 10, x >= 0, y <= 10, y >= 0]
>>> g2.prec() == Z3_GOAL_PRECISE
False
>>> g2.prec() == Z3_GOAL_UNDER
True

Definition at line 5695 of file z3py.py.

Referenced by Goal.precision().

    def prec(self):
        """Return the precision (under-approximation, over-approximation, or precise) of the goal `self`.

        >>> g = Goal()
        >>> g.prec() == Z3_GOAL_PRECISE
        True
        >>> x, y = Ints('x y')
        >>> g.add(x == y + 1)
        >>> g.prec() == Z3_GOAL_PRECISE
        True
        >>> t  = With(Tactic('add-bounds'), add_bound_lower=0, add_bound_upper=10)
        >>> g2 = t(g)[0]
        >>> g2
        [x == y + 1, x <= 10, x >= 0, y <= 10, y >= 0]
        >>> g2.prec() == Z3_GOAL_PRECISE
        False
        >>> g2.prec() == Z3_GOAL_UNDER
        True
        """
        return Z3_goal_precision(self.ctx.ref(), self.goal)

def precision

(

self

)

Alias for `prec()`.

>>> g = Goal()
>>> g.precision() == Z3_GOAL_PRECISE
True

Definition at line 5716 of file z3py.py.

    def precision(self):
        """Alias for `prec()`.

        >>> g = Goal()
        >>> g.precision() == Z3_GOAL_PRECISE
        True
        """
        return self.prec()

def sexpr

(

self

)

Return a textual representation of the s-expression representing the goal.

Definition at line 5859 of file z3py.py.

Referenced by Fixedpoint.__repr__(), and Optimize.__repr__().

    def sexpr(self):
        """Return a textual representation of the s-expression representing the goal."""
        return Z3_goal_to_string(self.ctx.ref(), self.goal)

def simplify	(		self,
			arguments,
			keywords
	)

Return a new simplified goal.

This method is essentially invoking the simplify tactic.

>>> g = Goal()
>>> x = Int('x')
>>> g.add(x + 1 >= 2)
>>> g
[x + 1 >= 2]
>>> g2 = g.simplify()
>>> g2
[x >= 1]
>>> # g was not modified
>>> g
[x + 1 >= 2]

Definition at line 5896 of file z3py.py.

    def simplify(self, *arguments, **keywords):
        """Return a new simplified goal.

        This method is essentially invoking the simplify tactic.

        >>> g = Goal()
        >>> x = Int('x')
        >>> g.add(x + 1 >= 2)
        >>> g
        [x + 1 >= 2]
        >>> g2 = g.simplify()
        >>> g2
        [x >= 1]
        >>> # g was not modified
        >>> g
        [x + 1 >= 2]
        """
        t = Tactic("simplify")
        return t.apply(self, *arguments, **keywords)[0]

def size

(

self

)

Return the number of constraints in the goal `self`.

>>> g = Goal()
>>> g.size()
0
>>> x, y = Ints('x y')
>>> g.add(x == 0, y > x)
>>> g.size()
2

Definition at line 5725 of file z3py.py.

Referenced by Goal.__len__().

    def size(self):
        """Return the number of constraints in the goal `self`.

        >>> g = Goal()
        >>> g.size()
        0
        >>> x, y = Ints('x y')
        >>> g.add(x == 0, y > x)
        >>> g.size()
        2
        """
        return int(Z3_goal_size(self.ctx.ref(), self.goal))

def translate	(		self,
			target
	)

Copy goal `self` to context `target`.

>>> x = Int('x')
>>> g = Goal()
>>> g.add(x > 10)
>>> g
[x > 10]
>>> c2 = Context()
>>> g2 = g.translate(c2)
>>> g2
[x > 10]
>>> g.ctx == main_ctx()
True
>>> g2.ctx == c2
True
>>> g2.ctx == main_ctx()
False

Definition at line 5867 of file z3py.py.

Referenced by Goal.__copy__(), AstVector.__copy__(), FuncInterp.__copy__(), Goal.__deepcopy__(), AstVector.__deepcopy__(), and FuncInterp.__deepcopy__().

    def translate(self, target):
        """Copy goal `self` to context `target`.

        >>> x = Int('x')
        >>> g = Goal()
        >>> g.add(x > 10)
        >>> g
        [x > 10]
        >>> c2 = Context()
        >>> g2 = g.translate(c2)
        >>> g2
        [x > 10]
        >>> g.ctx == main_ctx()
        True
        >>> g2.ctx == c2
        True
        >>> g2.ctx == main_ctx()
        False
        """
        if z3_debug():
            _z3_assert(isinstance(target, Context), "target must be a context")
        return Goal(goal=Z3_goal_translate(self.ctx.ref(), self.goal, target.ref()), ctx=target)

Field Documentation

ctx

Definition at line 5649 of file z3py.py.

Referenced by Goal.__copy__(), AstVector.__copy__(), FuncInterp.__copy__(), Goal.__deepcopy__(), AstVector.__deepcopy__(), AstMap.__deepcopy__(), FuncEntry.__deepcopy__(), FuncInterp.__deepcopy__(), Fixedpoint.__deepcopy__(), Optimize.__deepcopy__(), ApplyResult.__deepcopy__(), Simplifier.__deepcopy__(), Tactic.__deepcopy__(), Probe.__deepcopy__(), Probe.__eq__(), Probe.__ge__(), AstVector.__getitem__(), AstMap.__getitem__(), ApplyResult.__getitem__(), Probe.__gt__(), Probe.__le__(), Probe.__lt__(), Probe.__ne__(), Simplifier.add(), Fixedpoint.add_rule(), Optimize.add_soft(), Tactic.apply(), FuncEntry.arg_value(), Goal.as_expr(), ApplyResult.as_expr(), Optimize.assert_and_track(), Goal.assert_exprs(), Fixedpoint.assert_exprs(), Optimize.assert_exprs(), Optimize.assertions(), Goal.convert_model(), FuncInterp.else_value(), FuncInterp.entry(), ParserContext.from_string(), Goal.get(), Fixedpoint.get_answer(), Fixedpoint.get_assertions(), Fixedpoint.get_cover_delta(), Fixedpoint.get_ground_sat_answer(), Fixedpoint.get_rule_names_along_trace(), Fixedpoint.get_rules(), Fixedpoint.get_rules_along_trace(), AstMap.keys(), Optimize.model(), Optimize.objectives(), Fixedpoint.param_descrs(), Optimize.param_descrs(), Simplifier.param_descrs(), Tactic.param_descrs(), Fixedpoint.parse_file(), Fixedpoint.parse_string(), Fixedpoint.query(), Fixedpoint.set(), Optimize.set(), Optimize.set_on_model(), Tactic.solver(), Fixedpoint.statistics(), Optimize.statistics(), Solver.to_smt2(), Optimize.unsat_core(), Fixedpoint.update_rule(), Simplifier.using_params(), and FuncEntry.value().

goal

Definition at line 5650 of file z3py.py.

Referenced by Goal.__del__(), Goal.assert_exprs(), Goal.convert_model(), Goal.depth(), Goal.dimacs(), Goal.get(), Goal.inconsistent(), Goal.prec(), Goal.sexpr(), Goal.size(), and Goal.translate().