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Goal Class Reference
Inheritance diagram for Goal:

Public Member Functions

 __init__ (self, models=True, unsat_cores=False, proofs=False, ctx=None, goal=None)
 __del__ (self)
 depth (self)
 inconsistent (self)
 prec (self)
 precision (self)
 size (self)
 __len__ (self)
 get (self, i)
 __getitem__ (self, arg)
 assert_exprs (self, *args)
 append (self, *args)
 insert (self, *args)
 add (self, *args)
 convert_model (self, model)
 __repr__ (self)
 sexpr (self)
 dimacs (self, include_names=True)
 translate (self, target)
 __copy__ (self)
 __deepcopy__ (self, memo={})
 simplify (self, *arguments, **keywords)
 as_expr (self)
Public Member Functions inherited from Z3PPObject
 use_pp (self)

Data Fields

 ctx = _get_ctx(ctx)
 goal = goal

Additional Inherited Members

Protected Member Functions inherited from Z3PPObject
 _repr_html_ (self)

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 5666 of file z3py.py.

Constructor & Destructor Documentation

◆ __init__()

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

Definition at line 5674 of file z3py.py.

5674 def __init__(self, models=True, unsat_cores=False, proofs=False, ctx=None, goal=None):
5675 if z3_debug():
5676 _z3_assert(goal is None or ctx is not None,
5677 "If goal is different from None, then ctx must be also different from None")
5678 self.ctx = _get_ctx(ctx)
5679 self.goal = goal
5680 if self.goal is None:
5681 self.goal = Z3_mk_goal(self.ctx.ref(), models, unsat_cores, proofs)
5682 Z3_goal_inc_ref(self.ctx.ref(), self.goal)
5683
void Z3_API Z3_goal_inc_ref(Z3_context c, Z3_goal g)
Increment the reference counter of the given goal.
Z3_goal Z3_API Z3_mk_goal(Z3_context c, bool models, bool unsat_cores, bool proofs)
Create a goal (aka problem). A goal is essentially a set of formulas, that can be solved and/or trans...

◆ __del__()

__del__ ( self)

Definition at line 5684 of file z3py.py.

5684 def __del__(self):
5685 if self.goal is not None and self.ctx.ref() is not None and Z3_goal_dec_ref is not None:
5686 Z3_goal_dec_ref(self.ctx.ref(), self.goal)
5687
void Z3_API Z3_goal_dec_ref(Z3_context c, Z3_goal g)
Decrement the reference counter of the given goal.

Member Function Documentation

◆ __copy__()

__copy__ ( self)

Definition at line 5919 of file z3py.py.

5919 def __copy__(self):
5920 return self.translate(self.ctx)
5921

◆ __deepcopy__()

__deepcopy__ ( self,
memo = {} )

Definition at line 5922 of file z3py.py.

5922 def __deepcopy__(self, memo={}):
5923 return self.translate(self.ctx)
5924

◆ __getitem__()

__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 5793 of file z3py.py.

5793 def __getitem__(self, arg):
5794 """Return a constraint in the goal `self`.
5795
5796 >>> g = Goal()
5797 >>> x, y = Ints('x y')
5798 >>> g.add(x == 0, y > x)
5799 >>> g[0]
5800 x == 0
5801 >>> g[1]
5802 y > x
5803 """
5804 if arg >= len(self):
5805 raise IndexError
5806 return self.get(arg)
5807

◆ __len__()

__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 5767 of file z3py.py.

5767 def __len__(self):
5768 """Return the number of constraints in the goal `self`.
5769
5770 >>> g = Goal()
5771 >>> len(g)
5772 0
5773 >>> x, y = Ints('x y')
5774 >>> g.add(x == 0, y > x)
5775 >>> len(g)
5776 2
5777 """
5778 return self.size()
5779

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

◆ __repr__()

__repr__ ( self)

Definition at line 5885 of file z3py.py.

5885 def __repr__(self):
5886 return obj_to_string(self)
5887

◆ add()

add ( self,
* args )
Add constraints.

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

Definition at line 5845 of file z3py.py.

5845 def add(self, *args):
5846 """Add constraints.
5847
5848 >>> x = Int('x')
5849 >>> g = Goal()
5850 >>> g.add(x > 0, x < 2)
5851 >>> g
5852 [x > 0, x < 2]
5853 """
5854 self.assert_exprs(*args)
5855

Referenced by Solver.__iadd__().

◆ append()

append ( self,
* args )
Add constraints.

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

Definition at line 5823 of file z3py.py.

5823 def append(self, *args):
5824 """Add constraints.
5825
5826 >>> x = Int('x')
5827 >>> g = Goal()
5828 >>> g.append(x > 0, x < 2)
5829 >>> g
5830 [x > 0, x < 2]
5831 """
5832 self.assert_exprs(*args)
5833

◆ as_expr()

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 5945 of file z3py.py.

5945 def as_expr(self):
5946 """Return goal `self` as a single Z3 expression.
5947
5948 >>> x = Int('x')
5949 >>> g = Goal()
5950 >>> g.as_expr()
5951 True
5952 >>> g.add(x > 1)
5953 >>> g.as_expr()
5954 x > 1
5955 >>> g.add(x < 10)
5956 >>> g.as_expr()
5957 And(x > 1, x < 10)
5958 """
5959 sz = len(self)
5960 if sz == 0:
5961 return BoolVal(True, self.ctx)
5962 elif sz == 1:
5963 return self.get(0)
5964 else:
5965 return And([self.get(i) for i in range(len(self))], self.ctx)
5966

◆ assert_exprs()

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 5808 of file z3py.py.

5808 def assert_exprs(self, *args):
5809 """Assert constraints into the goal.
5810
5811 >>> x = Int('x')
5812 >>> g = Goal()
5813 >>> g.assert_exprs(x > 0, x < 2)
5814 >>> g
5815 [x > 0, x < 2]
5816 """
5817 args = _get_args(args)
5818 s = BoolSort(self.ctx)
5819 for arg in args:
5820 arg = s.cast(arg)
5821 Z3_goal_assert(self.ctx.ref(), self.goal, arg.as_ast())
5822
void Z3_API Z3_goal_assert(Z3_context c, Z3_goal g, Z3_ast a)
Add a new formula a to the given goal. The formula is split according to the following procedure that...

Referenced by add(), Solver.add(), append(), Solver.append(), insert(), and Solver.insert().

◆ convert_model()

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 5856 of file z3py.py.

5856 def convert_model(self, model):
5857 """Retrieve model from a satisfiable goal
5858 >>> a, b = Ints('a b')
5859 >>> g = Goal()
5860 >>> g.add(Or(a == 0, a == 1), Or(b == 0, b == 1), a > b)
5861 >>> t = Then(Tactic('split-clause'), Tactic('solve-eqs'))
5862 >>> r = t(g)
5863 >>> r[0]
5864 [Or(b == 0, b == 1), Not(0 <= b)]
5865 >>> r[1]
5866 [Or(b == 0, b == 1), Not(1 <= b)]
5867 >>> # Remark: the subgoal r[0] is unsatisfiable
5868 >>> # Creating a solver for solving the second subgoal
5869 >>> s = Solver()
5870 >>> s.add(r[1])
5871 >>> s.check()
5872 sat
5873 >>> s.model()
5874 [b = 0]
5875 >>> # Model s.model() does not assign a value to `a`
5876 >>> # It is a model for subgoal `r[1]`, but not for goal `g`
5877 >>> # The method convert_model creates a model for `g` from a model for `r[1]`.
5878 >>> r[1].convert_model(s.model())
5879 [b = 0, a = 1]
5880 """
5881 if z3_debug():
5882 _z3_assert(isinstance(model, ModelRef), "Z3 Model expected")
5883 return ModelRef(Z3_goal_convert_model(self.ctx.ref(), self.goal, model.model), self.ctx)
5884
Z3_model Z3_API Z3_goal_convert_model(Z3_context c, Z3_goal g, Z3_model m)
Convert a model of the formulas of a goal to a model of an original goal. The model may be null,...

◆ depth()

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 5688 of file z3py.py.

5688 def depth(self):
5689 """Return the depth of the goal `self`.
5690 The depth corresponds to the number of tactics applied to `self`.
5691
5692 >>> x, y = Ints('x y')
5693 >>> g = Goal()
5694 >>> g.add(x == 0, y >= x + 1)
5695 >>> g.depth()
5696 0
5697 >>> r = Then('simplify', 'solve-eqs')(g)
5698 >>> # r has 1 subgoal
5699 >>> len(r)
5700 1
5701 >>> r[0].depth()
5702 2
5703 """
5704 return int(Z3_goal_depth(self.ctx.ref(), self.goal))
5705
unsigned Z3_API Z3_goal_depth(Z3_context c, Z3_goal g)
Return the depth of the given goal. It tracks how many transformations were applied to it.

◆ dimacs()

dimacs ( self,
include_names = True )
Return a textual representation of the goal in DIMACS format.

Definition at line 5892 of file z3py.py.

5892 def dimacs(self, include_names=True):
5893 """Return a textual representation of the goal in DIMACS format."""
5894 return Z3_goal_to_dimacs_string(self.ctx.ref(), self.goal, include_names)
5895
Z3_string Z3_API Z3_goal_to_dimacs_string(Z3_context c, Z3_goal g, bool include_names)
Convert a goal into a DIMACS formatted string. The goal must be in CNF. You can convert a goal to CNF...

◆ get()

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 5780 of file z3py.py.

5780 def get(self, i):
5781 """Return a constraint in the goal `self`.
5782
5783 >>> g = Goal()
5784 >>> x, y = Ints('x y')
5785 >>> g.add(x == 0, y > x)
5786 >>> g.get(0)
5787 x == 0
5788 >>> g.get(1)
5789 y > x
5790 """
5791 return _to_expr_ref(Z3_goal_formula(self.ctx.ref(), self.goal, i), self.ctx)
5792
Z3_ast Z3_API Z3_goal_formula(Z3_context c, Z3_goal g, unsigned idx)
Return a formula from the given goal.

Referenced by __getitem__(), and as_expr().

◆ inconsistent()

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 5706 of file z3py.py.

5706 def inconsistent(self):
5707 """Return `True` if `self` contains the `False` constraints.
5708
5709 >>> x, y = Ints('x y')
5710 >>> g = Goal()
5711 >>> g.inconsistent()
5712 False
5713 >>> g.add(x == 0, x == 1)
5714 >>> g
5715 [x == 0, x == 1]
5716 >>> g.inconsistent()
5717 False
5718 >>> g2 = Tactic('propagate-values')(g)[0]
5719 >>> g2.inconsistent()
5720 True
5721 """
5722 return Z3_goal_inconsistent(self.ctx.ref(), self.goal)
5723
bool Z3_API Z3_goal_inconsistent(Z3_context c, Z3_goal g)
Return true if the given goal contains the formula false.

◆ insert()

insert ( self,
* args )
Add constraints.

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

Definition at line 5834 of file z3py.py.

5834 def insert(self, *args):
5835 """Add constraints.
5836
5837 >>> x = Int('x')
5838 >>> g = Goal()
5839 >>> g.insert(x > 0, x < 2)
5840 >>> g
5841 [x > 0, x < 2]
5842 """
5843 self.assert_exprs(*args)
5844

◆ prec()

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 5724 of file z3py.py.

5724 def prec(self):
5725 """Return the precision (under-approximation, over-approximation, or precise) of the goal `self`.
5726
5727 >>> g = Goal()
5728 >>> g.prec() == Z3_GOAL_PRECISE
5729 True
5730 >>> x, y = Ints('x y')
5731 >>> g.add(x == y + 1)
5732 >>> g.prec() == Z3_GOAL_PRECISE
5733 True
5734 >>> t = With(Tactic('add-bounds'), add_bound_lower=0, add_bound_upper=10)
5735 >>> g2 = t(g)[0]
5736 >>> g2
5737 [x == y + 1, x <= 10, x >= 0, y <= 10, y >= 0]
5738 >>> g2.prec() == Z3_GOAL_PRECISE
5739 False
5740 >>> g2.prec() == Z3_GOAL_UNDER
5741 True
5742 """
5743 return Z3_goal_precision(self.ctx.ref(), self.goal)
5744
Z3_goal_prec Z3_API Z3_goal_precision(Z3_context c, Z3_goal g)
Return the "precision" of the given goal. Goals can be transformed using over and under approximation...

Referenced by precision().

◆ precision()

precision ( self)
Alias for `prec()`.

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

Definition at line 5745 of file z3py.py.

5745 def precision(self):
5746 """Alias for `prec()`.
5747
5748 >>> g = Goal()
5749 >>> g.precision() == Z3_GOAL_PRECISE
5750 True
5751 """
5752 return self.prec()
5753

◆ sexpr()

sexpr ( self)
Return a textual representation of the s-expression representing the goal.

Definition at line 5888 of file z3py.py.

5888 def sexpr(self):
5889 """Return a textual representation of the s-expression representing the goal."""
5890 return Z3_goal_to_string(self.ctx.ref(), self.goal)
5891
Z3_string Z3_API Z3_goal_to_string(Z3_context c, Z3_goal g)
Convert a goal into a string.

◆ simplify()

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 5925 of file z3py.py.

5925 def simplify(self, *arguments, **keywords):
5926 """Return a new simplified goal.
5927
5928 This method is essentially invoking the simplify tactic.
5929
5930 >>> g = Goal()
5931 >>> x = Int('x')
5932 >>> g.add(x + 1 >= 2)
5933 >>> g
5934 [x + 1 >= 2]
5935 >>> g2 = g.simplify()
5936 >>> g2
5937 [x >= 1]
5938 >>> # g was not modified
5939 >>> g
5940 [x + 1 >= 2]
5941 """
5942 t = Tactic("simplify")
5943 return t.apply(self, *arguments, **keywords)[0]
5944

◆ size()

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 5754 of file z3py.py.

5754 def size(self):
5755 """Return the number of constraints in the goal `self`.
5756
5757 >>> g = Goal()
5758 >>> g.size()
5759 0
5760 >>> x, y = Ints('x y')
5761 >>> g.add(x == 0, y > x)
5762 >>> g.size()
5763 2
5764 """
5765 return int(Z3_goal_size(self.ctx.ref(), self.goal))
5766
unsigned Z3_API Z3_goal_size(Z3_context c, Z3_goal g)
Return the number of formulas in the given goal.

Referenced by __len__().

◆ translate()

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 5896 of file z3py.py.

5896 def translate(self, target):
5897 """Copy goal `self` to context `target`.
5898
5899 >>> x = Int('x')
5900 >>> g = Goal()
5901 >>> g.add(x > 10)
5902 >>> g
5903 [x > 10]
5904 >>> c2 = Context()
5905 >>> g2 = g.translate(c2)
5906 >>> g2
5907 [x > 10]
5908 >>> g.ctx == main_ctx()
5909 True
5910 >>> g2.ctx == c2
5911 True
5912 >>> g2.ctx == main_ctx()
5913 False
5914 """
5915 if z3_debug():
5916 _z3_assert(isinstance(target, Context), "target must be a context")
5917 return Goal(goal=Z3_goal_translate(self.ctx.ref(), self.goal, target.ref()), ctx=target)
5918
Z3_goal Z3_API Z3_goal_translate(Z3_context source, Z3_goal g, Z3_context target)
Copy a goal g from the context source to the context target.

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

Field Documentation

◆ ctx

ctx = _get_ctx(ctx)

Definition at line 5678 of file z3py.py.

Referenced by AstMap.__contains__(), AstVector.__copy__(), FuncInterp.__copy__(), __copy__(), ModelRef.__copy__(), AstMap.__deepcopy__(), AstVector.__deepcopy__(), FuncEntry.__deepcopy__(), FuncInterp.__deepcopy__(), __deepcopy__(), ModelRef.__deepcopy__(), Statistics.__deepcopy__(), AstMap.__del__(), AstVector.__del__(), FuncEntry.__del__(), FuncInterp.__del__(), __del__(), ModelRef.__del__(), Solver.__del__(), Statistics.__del__(), AstMap.__getitem__(), AstVector.__getitem__(), ModelRef.__getitem__(), Statistics.__getitem__(), AstMap.__len__(), AstVector.__len__(), ModelRef.__len__(), Statistics.__len__(), AstMap.__repr__(), Statistics.__repr__(), AstMap.__setitem__(), AstVector.__setitem__(), FuncEntry.arg_value(), FuncInterp.arity(), as_expr(), Solver.assert_and_track(), assert_exprs(), Solver.assert_exprs(), Solver.check(), convert_model(), ModelRef.decls(), depth(), dimacs(), FuncInterp.else_value(), FuncInterp.entry(), AstMap.erase(), ModelRef.eval(), get(), ModelRef.get_interp(), Statistics.get_key_value(), ModelRef.get_sort(), ModelRef.get_universe(), inconsistent(), AstMap.keys(), Statistics.keys(), Solver.model(), FuncEntry.num_args(), FuncInterp.num_entries(), Solver.num_scopes(), ModelRef.num_sorts(), Solver.pop(), prec(), ModelRef.project(), ModelRef.project_with_witness(), AstVector.push(), Solver.push(), AstMap.reset(), Solver.reset(), AstVector.resize(), Solver.set(), AstVector.sexpr(), sexpr(), ModelRef.sexpr(), size(), AstVector.translate(), translate(), ModelRef.translate(), and FuncEntry.value().

◆ goal

goal = goal