ExprRef Class Reference

Expressions. More...

Inheritance diagram for ExprRef:

Public Member Functions
def	as_ast (self)
def	get_id (self)
def	sort (self)
def	sort_kind (self)
def	__eq__ (self, other)
def	__hash__ (self)
def	__ne__ (self, other)
def	decl (self)
def	num_args (self)
def	arg (self, idx)
def	children (self)
Public Member Functions inherited from AstRef
def	__init__ (self, ast, ctx=None)
def	__del__ (self)
def	__str__ (self)
def	__repr__ (self)
def	__nonzero__ (self)
def	__bool__ (self)
def	sexpr (self)
def	ctx_ref (self)
def	eq (self, other)
def	translate (self, target)
def	hash (self)
Public Member Functions inherited from Z3PPObject
def	use_pp (self)

Additional Inherited Members
Data Fields inherited from AstRef
	ast
	ctx

Detailed Description

Expressions.

Constraints, formulas and terms are expressions in Z3.

Expressions are ASTs. Every expression has a sort.
There are three main kinds of expressions:
function applications, quantifiers and bounded variables.
A constant is a function application with 0 arguments.
For quantifier free problems, all expressions are
function applications.

Definition at line 769 of file z3py.py.

Member Function Documentation

__eq__()

def __eq__	(		self,
			other
	)

Return a Z3 expression that represents the constraint `self == other`.

If `other` is `None`, then this method simply returns `False`.

>>> a = Int('a')
>>> b = Int('b')
>>> a == b
a == b
>>> a is None
False

Reimplemented from AstRef.

Definition at line 808 of file z3py.py.

    def __eq__(self, other):
        """Return a Z3 expression that represents the constraint `self == other`.

        If `other` is `None`, then this method simply returns `False`.

        >>> a = Int('a')
        >>> b = Int('b')
        >>> a == b
        a == b
        >>> a is None
        False
        """
        if other is None:
            return False
        a, b = _coerce_exprs(self, other)
        return BoolRef(Z3_mk_eq(self.ctx_ref(), a.as_ast(), b.as_ast()), self.ctx)

Referenced by CheckSatResult.__ne__(), and Probe.__ne__().

__hash__()

def __hash__

(

self

)

Hash code. 

Reimplemented from AstRef.

Definition at line 825 of file z3py.py.

    def __hash__(self):
        """ Hash code. """
        return AstRef.__hash__(self)

__ne__()

def __ne__	(		self,
			other
	)

Return a Z3 expression that represents the constraint `self != other`.

If `other` is `None`, then this method simply returns `True`.

>>> a = Int('a')
>>> b = Int('b')
>>> a != b
a != b
>>> a is not None
True

Definition at line 829 of file z3py.py.

    def __ne__(self, other):
        """Return a Z3 expression that represents the constraint `self != other`.

        If `other` is `None`, then this method simply returns `True`.

        >>> a = Int('a')
        >>> b = Int('b')
        >>> a != b
        a != b
        >>> a is not None
        True
        """
        if other is None:
            return True
        a, b = _coerce_exprs(self, other)
        _args, sz = _to_ast_array((a, b))
        return BoolRef(Z3_mk_distinct(self.ctx_ref(), 2, _args), self.ctx)

arg()

def arg	(		self,
			idx
	)

Return argument `idx` of the application `self`.

This method assumes that `self` is a function application with at least `idx+1` arguments.

>>> a = Int('a')
>>> b = Int('b')
>>> f = Function('f', IntSort(), IntSort(), IntSort(), IntSort())
>>> t = f(a, b, 0)
>>> t.arg(0)
a
>>> t.arg(1)
b
>>> t.arg(2)
0

Definition at line 878 of file z3py.py.

    def arg(self, idx):
        """Return argument `idx` of the application `self`.

        This method assumes that `self` is a function application with at least `idx+1` arguments.

        >>> a = Int('a')
        >>> b = Int('b')
        >>> f = Function('f', IntSort(), IntSort(), IntSort(), IntSort())
        >>> t = f(a, b, 0)
        >>> t.arg(0)
        a
        >>> t.arg(1)
        b
        >>> t.arg(2)
        0
        """
        if __debug__:
            _z3_assert(is_app(self), "Z3 application expected")
            _z3_assert(idx < self.num_args(), "Invalid argument index")
        return _to_expr_ref(Z3_get_app_arg(self.ctx_ref(), self.as_ast(), idx), self.ctx)

Referenced by AstRef.__bool__(), and ExprRef.children().

as_ast()

def as_ast

(

self

)

Return a pointer to the corresponding C Z3_ast object.

Reimplemented from AstRef.

Reimplemented in QuantifierRef, and PatternRef.

Definition at line 779 of file z3py.py.

    def as_ast(self):
        return self.ast

children()

def children

(

self

)

Return a list containing the children of the given expression

>>> a = Int('a')
>>> b = Int('b')
>>> f = Function('f', IntSort(), IntSort(), IntSort(), IntSort())
>>> t = f(a, b, 0)
>>> t.children()
[a, b, 0]

Reimplemented in QuantifierRef.

Definition at line 899 of file z3py.py.

    def children(self):
        """Return a list containing the children of the given expression

        >>> a = Int('a')
        >>> b = Int('b')
        >>> f = Function('f', IntSort(), IntSort(), IntSort(), IntSort())
        >>> t = f(a, b, 0)
        >>> t.children()
        [a, b, 0]
        """
        if is_app(self):
            return [self.arg(i) for i in range(self.num_args())]
        else:
            return []

decl()

def decl

(

self

)

Return the Z3 function declaration associated with a Z3 application.

>>> f = Function('f', IntSort(), IntSort())
>>> a = Int('a')
>>> t = f(a)
>>> eq(t.decl(), f)
True
>>> (a + 1).decl()
+

Definition at line 847 of file z3py.py.

    def decl(self):
        """Return the Z3 function declaration associated with a Z3 application.

        >>> f = Function('f', IntSort(), IntSort())
        >>> a = Int('a')
        >>> t = f(a)
        >>> eq(t.decl(), f)
        True
        >>> (a + 1).decl()
        +
        """
        if __debug__:
            _z3_assert(is_app(self), "Z3 application expected")
        return FuncDeclRef(Z3_get_app_decl(self.ctx_ref(), self.as_ast()), self.ctx)

Referenced by FPNumRef.isInf(), FPNumRef.isNaN(), FPNumRef.isNegative(), and FPNumRef.isZero().

get_id()

def get_id

(

self

)

Return unique identifier for object. It can be used for hash-tables and maps.

Reimplemented from AstRef.

Reimplemented in QuantifierRef, and PatternRef.

Definition at line 782 of file z3py.py.

    def get_id(self):
        return Z3_get_ast_id(self.ctx_ref(), self.as_ast())

num_args()

def num_args

(

self

)

Return the number of arguments of a Z3 application.

>>> a = Int('a')
>>> b = Int('b')
>>> (a + b).num_args()
2
>>> f = Function('f', IntSort(), IntSort(), IntSort(), IntSort())
>>> t = f(a, b, 0)
>>> t.num_args()
3

Definition at line 862 of file z3py.py.

    def num_args(self):
        """Return the number of arguments of a Z3 application.

        >>> a = Int('a')
        >>> b = Int('b')
        >>> (a + b).num_args()
        2
        >>> f = Function('f', IntSort(), IntSort(), IntSort(), IntSort())
        >>> t = f(a, b, 0)
        >>> t.num_args()
        3
        """
        if __debug__:
            _z3_assert(is_app(self), "Z3 application expected")
        return int(Z3_get_app_num_args(self.ctx_ref(), self.as_ast()))

Referenced by AstRef.__bool__(), ExprRef.arg(), FuncEntry.arg_value(), FuncEntry.as_list(), ExprRef.children(), and FPNumRef.isNegative().

sort()

def sort

(

self

)

Return the sort of expression `self`.

>>> x = Int('x')
>>> (x + 1).sort()
Int
>>> y = Real('y')
>>> (x + y).sort()
Real

Reimplemented in SeqRef, FPRef, FiniteDomainRef, DatatypeRef, ArrayRef, BitVecRef, ArithRef, QuantifierRef, and BoolRef.

Definition at line 785 of file z3py.py.

    def sort(self):
        """Return the sort of expression `self`.

        >>> x = Int('x')
        >>> (x + 1).sort()
        Int
        >>> y = Real('y')
        >>> (x + y).sort()
        Real
        """
        return _sort(self.ctx, self.as_ast())

Referenced by FPNumRef.as_string(), ArrayRef.domain(), FPRef.ebits(), ArithRef.is_int(), ArithRef.is_real(), ArrayRef.range(), FPRef.sbits(), BitVecRef.size(), and ExprRef.sort_kind().

sort_kind()

def sort_kind

(

self

)

Shorthand for `self.sort().kind()`.

>>> a = Array('a', IntSort(), IntSort())
>>> a.sort_kind() == Z3_ARRAY_SORT
True
>>> a.sort_kind() == Z3_INT_SORT
False

Definition at line 797 of file z3py.py.

    def sort_kind(self):
        """Shorthand for `self.sort().kind()`.

        >>> a = Array('a', IntSort(), IntSort())
        >>> a.sort_kind() == Z3_ARRAY_SORT
        True
        >>> a.sort_kind() == Z3_INT_SORT
        False
        """
        return self.sort().kind()