Z3
Public Member Functions | Data Fields
Tactic Class Reference

Public Member Functions

def __init__ (self, tactic, ctx=None)
 
def __del__ (self)
 
def solver (self)
 
def apply (self, goal, arguments, keywords)
 
def __call__ (self, goal, arguments, keywords)
 
def help (self)
 
def param_descrs (self)
 

Data Fields

 ctx
 
 tactic
 

Detailed Description

Tactics transform, solver and/or simplify sets of constraints (Goal). A Tactic can be converted into a Solver using the method solver().

Several combinators are available for creating new tactics using the built-in ones: Then(), OrElse(), FailIf(), Repeat(), When(), Cond().

Definition at line 6946 of file z3py.py.

Constructor & Destructor Documentation

§ __init__()

def __init__ (   self,
  tactic,
  ctx = None 
)

Definition at line 6951 of file z3py.py.

6951  def __init__(self, tactic, ctx=None):
6952  self.ctx = _get_ctx(ctx)
6953  self.tactic = None
6954  if isinstance(tactic, TacticObj):
6955  self.tactic = tactic
6956  else:
6957  if __debug__:
6958  _z3_assert(isinstance(tactic, str), "tactic name expected")
6959  try:
6960  self.tactic = Z3_mk_tactic(self.ctx.ref(), str(tactic))
6961  except Z3Exception:
6962  raise Z3Exception("unknown tactic '%s'" % tactic)
6963  Z3_tactic_inc_ref(self.ctx.ref(), self.tactic)
6964 
void Z3_API Z3_tactic_inc_ref(Z3_context c, Z3_tactic t)
Increment the reference counter of the given tactic.
Z3_tactic Z3_API Z3_mk_tactic(Z3_context c, Z3_string name)
Return a tactic associated with the given name. The complete list of tactics may be obtained using th...

§ __del__()

def __del__ (   self)

Definition at line 6965 of file z3py.py.

6965  def __del__(self):
6966  if self.tactic is not None and self.ctx.ref() is not None:
6967  Z3_tactic_dec_ref(self.ctx.ref(), self.tactic)
6968 
void Z3_API Z3_tactic_dec_ref(Z3_context c, Z3_tactic g)
Decrement the reference counter of the given tactic.

Member Function Documentation

§ __call__()

def __call__ (   self,
  goal,
  arguments,
  keywords 
)
Apply tactic `self` to the given goal or Z3 Boolean expression using the given options.

>>> x, y = Ints('x y')
>>> t = Tactic('solve-eqs')
>>> t(And(x == 0, y >= x + 1))
[[y >= 1]]

Definition at line 7003 of file z3py.py.

7003  def __call__(self, goal, *arguments, **keywords):
7004  """Apply tactic `self` to the given goal or Z3 Boolean expression using the given options.
7005 
7006  >>> x, y = Ints('x y')
7007  >>> t = Tactic('solve-eqs')
7008  >>> t(And(x == 0, y >= x + 1))
7009  [[y >= 1]]
7010  """
7011  return self.apply(goal, *arguments, **keywords)
7012 

§ apply()

def apply (   self,
  goal,
  arguments,
  keywords 
)
Apply tactic `self` to the given goal or Z3 Boolean expression using the given options.

>>> x, y = Ints('x y')
>>> t = Tactic('solve-eqs')
>>> t.apply(And(x == 0, y >= x + 1))
[[y >= 1]]

Definition at line 6986 of file z3py.py.

Referenced by Tactic.__call__().

6986  def apply(self, goal, *arguments, **keywords):
6987  """Apply tactic `self` to the given goal or Z3 Boolean expression using the given options.
6988 
6989  >>> x, y = Ints('x y')
6990  >>> t = Tactic('solve-eqs')
6991  >>> t.apply(And(x == 0, y >= x + 1))
6992  [[y >= 1]]
6993  """
6994  if __debug__:
6995  _z3_assert(isinstance(goal, Goal) or isinstance(goal, BoolRef), "Z3 Goal or Boolean expressions expected")
6996  goal = _to_goal(goal)
6997  if len(arguments) > 0 or len(keywords) > 0:
6998  p = args2params(arguments, keywords, self.ctx)
6999  return ApplyResult(Z3_tactic_apply_ex(self.ctx.ref(), self.tactic, goal.goal, p.params), self.ctx)
7000  else:
7001  return ApplyResult(Z3_tactic_apply(self.ctx.ref(), self.tactic, goal.goal), self.ctx)
7002 
def args2params(arguments, keywords, ctx=None)
Definition: z3py.py:4644
Z3_apply_result Z3_API Z3_tactic_apply(Z3_context c, Z3_tactic t, Z3_goal g)
Apply tactic t to the goal g.
Z3_apply_result Z3_API Z3_tactic_apply_ex(Z3_context c, Z3_tactic t, Z3_goal g, Z3_params p)
Apply tactic t to the goal g using the parameter set p.

§ help()

def help (   self)
Display a string containing a description of the available options for the `self` tactic.

Definition at line 7013 of file z3py.py.

7013  def help(self):
7014  """Display a string containing a description of the available options for the `self` tactic."""
7015  print(Z3_tactic_get_help(self.ctx.ref(), self.tactic))
7016 
Z3_string Z3_API Z3_tactic_get_help(Z3_context c, Z3_tactic t)
Return a string containing a description of parameters accepted by the given tactic.

§ param_descrs()

def param_descrs (   self)
Return the parameter description set.

Definition at line 7017 of file z3py.py.

7017  def param_descrs(self):
7018  """Return the parameter description set."""
7019  return ParamDescrsRef(Z3_tactic_get_param_descrs(self.ctx.ref(), self.tactic), self.ctx)
7020 
Z3_param_descrs Z3_API Z3_tactic_get_param_descrs(Z3_context c, Z3_tactic t)
Return the parameter description set for the given tactic object.

§ solver()

def solver (   self)
Create a solver using the tactic `self`.

The solver supports the methods `push()` and `pop()`, but it
will always solve each `check()` from scratch.

>>> t = Then('simplify', 'nlsat')
>>> s = t.solver()
>>> x = Real('x')
>>> s.add(x**2 == 2, x > 0)
>>> s.check()
sat
>>> s.model()
[x = 1.4142135623?]

Definition at line 6969 of file z3py.py.

6969  def solver(self):
6970  """Create a solver using the tactic `self`.
6971 
6972  The solver supports the methods `push()` and `pop()`, but it
6973  will always solve each `check()` from scratch.
6974 
6975  >>> t = Then('simplify', 'nlsat')
6976  >>> s = t.solver()
6977  >>> x = Real('x')
6978  >>> s.add(x**2 == 2, x > 0)
6979  >>> s.check()
6980  sat
6981  >>> s.model()
6982  [x = 1.4142135623?]
6983  """
6984  return Solver(Z3_mk_solver_from_tactic(self.ctx.ref(), self.tactic), self.ctx)
6985 
Z3_solver Z3_API Z3_mk_solver_from_tactic(Z3_context c, Z3_tactic t)
Create a new solver that is implemented using the given tactic. The solver supports the commands Z3_s...

Field Documentation

§ ctx

ctx

§ tactic

tactic