mirror of
https://github.com/SickGear/SickGear.git
synced 2024-12-01 00:43:37 +00:00
867 lines
21 KiB
Python
867 lines
21 KiB
Python
# sql/operators.py
|
|
# Copyright (C) 2005-2014 the SQLAlchemy authors and contributors <see AUTHORS file>
|
|
#
|
|
# This module is part of SQLAlchemy and is released under
|
|
# the MIT License: http://www.opensource.org/licenses/mit-license.php
|
|
|
|
# This module is part of SQLAlchemy and is released under
|
|
# the MIT License: http://www.opensource.org/licenses/mit-license.php
|
|
|
|
"""Defines operators used in SQL expressions."""
|
|
|
|
from .. import util
|
|
|
|
|
|
from operator import (
|
|
and_, or_, inv, add, mul, sub, mod, truediv, lt, le, ne, gt, ge, eq, neg,
|
|
getitem, lshift, rshift
|
|
)
|
|
|
|
if util.py2k:
|
|
from operator import div
|
|
else:
|
|
div = truediv
|
|
|
|
|
|
|
|
class Operators(object):
|
|
"""Base of comparison and logical operators.
|
|
|
|
Implements base methods :meth:`~sqlalchemy.sql.operators.Operators.operate` and
|
|
:meth:`~sqlalchemy.sql.operators.Operators.reverse_operate`, as well as
|
|
:meth:`~sqlalchemy.sql.operators.Operators.__and__`,
|
|
:meth:`~sqlalchemy.sql.operators.Operators.__or__`,
|
|
:meth:`~sqlalchemy.sql.operators.Operators.__invert__`.
|
|
|
|
Usually is used via its most common subclass
|
|
:class:`.ColumnOperators`.
|
|
|
|
"""
|
|
def __and__(self, other):
|
|
"""Implement the ``&`` operator.
|
|
|
|
When used with SQL expressions, results in an
|
|
AND operation, equivalent to
|
|
:func:`~.expression.and_`, that is::
|
|
|
|
a & b
|
|
|
|
is equivalent to::
|
|
|
|
from sqlalchemy import and_
|
|
and_(a, b)
|
|
|
|
Care should be taken when using ``&`` regarding
|
|
operator precedence; the ``&`` operator has the highest precedence.
|
|
The operands should be enclosed in parenthesis if they contain
|
|
further sub expressions::
|
|
|
|
(a == 2) & (b == 4)
|
|
|
|
"""
|
|
return self.operate(and_, other)
|
|
|
|
def __or__(self, other):
|
|
"""Implement the ``|`` operator.
|
|
|
|
When used with SQL expressions, results in an
|
|
OR operation, equivalent to
|
|
:func:`~.expression.or_`, that is::
|
|
|
|
a | b
|
|
|
|
is equivalent to::
|
|
|
|
from sqlalchemy import or_
|
|
or_(a, b)
|
|
|
|
Care should be taken when using ``|`` regarding
|
|
operator precedence; the ``|`` operator has the highest precedence.
|
|
The operands should be enclosed in parenthesis if they contain
|
|
further sub expressions::
|
|
|
|
(a == 2) | (b == 4)
|
|
|
|
"""
|
|
return self.operate(or_, other)
|
|
|
|
def __invert__(self):
|
|
"""Implement the ``~`` operator.
|
|
|
|
When used with SQL expressions, results in a
|
|
NOT operation, equivalent to
|
|
:func:`~.expression.not_`, that is::
|
|
|
|
~a
|
|
|
|
is equivalent to::
|
|
|
|
from sqlalchemy import not_
|
|
not_(a)
|
|
|
|
"""
|
|
return self.operate(inv)
|
|
|
|
def op(self, opstring, precedence=0, is_comparison=False):
|
|
"""produce a generic operator function.
|
|
|
|
e.g.::
|
|
|
|
somecolumn.op("*")(5)
|
|
|
|
produces::
|
|
|
|
somecolumn * 5
|
|
|
|
This function can also be used to make bitwise operators explicit. For
|
|
example::
|
|
|
|
somecolumn.op('&')(0xff)
|
|
|
|
is a bitwise AND of the value in ``somecolumn``.
|
|
|
|
:param operator: a string which will be output as the infix operator
|
|
between this element and the expression passed to the
|
|
generated function.
|
|
|
|
:param precedence: precedence to apply to the operator, when
|
|
parenthesizing expressions. A lower number will cause the expression
|
|
to be parenthesized when applied against another operator with
|
|
higher precedence. The default value of ``0`` is lower than all
|
|
operators except for the comma (``,``) and ``AS`` operators.
|
|
A value of 100 will be higher or equal to all operators, and -100
|
|
will be lower than or equal to all operators.
|
|
|
|
.. versionadded:: 0.8 - added the 'precedence' argument.
|
|
|
|
:param is_comparison: if True, the operator will be considered as a
|
|
"comparison" operator, that is which evaulates to a boolean true/false
|
|
value, like ``==``, ``>``, etc. This flag should be set so that
|
|
ORM relationships can establish that the operator is a comparison
|
|
operator when used in a custom join condition.
|
|
|
|
.. versionadded:: 0.9.2 - added the :paramref:`.Operators.op.is_comparison`
|
|
flag.
|
|
|
|
.. seealso::
|
|
|
|
:ref:`types_operators`
|
|
|
|
:ref:`relationship_custom_operator`
|
|
|
|
"""
|
|
operator = custom_op(opstring, precedence, is_comparison)
|
|
|
|
def against(other):
|
|
return operator(self, other)
|
|
return against
|
|
|
|
def operate(self, op, *other, **kwargs):
|
|
"""Operate on an argument.
|
|
|
|
This is the lowest level of operation, raises
|
|
:class:`NotImplementedError` by default.
|
|
|
|
Overriding this on a subclass can allow common
|
|
behavior to be applied to all operations.
|
|
For example, overriding :class:`.ColumnOperators`
|
|
to apply ``func.lower()`` to the left and right
|
|
side::
|
|
|
|
class MyComparator(ColumnOperators):
|
|
def operate(self, op, other):
|
|
return op(func.lower(self), func.lower(other))
|
|
|
|
:param op: Operator callable.
|
|
:param \*other: the 'other' side of the operation. Will
|
|
be a single scalar for most operations.
|
|
:param \**kwargs: modifiers. These may be passed by special
|
|
operators such as :meth:`ColumnOperators.contains`.
|
|
|
|
|
|
"""
|
|
raise NotImplementedError(str(op))
|
|
|
|
def reverse_operate(self, op, other, **kwargs):
|
|
"""Reverse operate on an argument.
|
|
|
|
Usage is the same as :meth:`operate`.
|
|
|
|
"""
|
|
raise NotImplementedError(str(op))
|
|
|
|
|
|
class custom_op(object):
|
|
"""Represent a 'custom' operator.
|
|
|
|
:class:`.custom_op` is normally instantitated when the
|
|
:meth:`.ColumnOperators.op` method is used to create a
|
|
custom operator callable. The class can also be used directly
|
|
when programmatically constructing expressions. E.g.
|
|
to represent the "factorial" operation::
|
|
|
|
from sqlalchemy.sql import UnaryExpression
|
|
from sqlalchemy.sql import operators
|
|
from sqlalchemy import Numeric
|
|
|
|
unary = UnaryExpression(table.c.somecolumn,
|
|
modifier=operators.custom_op("!"),
|
|
type_=Numeric)
|
|
|
|
"""
|
|
__name__ = 'custom_op'
|
|
|
|
def __init__(self, opstring, precedence=0, is_comparison=False):
|
|
self.opstring = opstring
|
|
self.precedence = precedence
|
|
self.is_comparison = is_comparison
|
|
|
|
def __eq__(self, other):
|
|
return isinstance(other, custom_op) and \
|
|
other.opstring == self.opstring
|
|
|
|
def __hash__(self):
|
|
return id(self)
|
|
|
|
def __call__(self, left, right, **kw):
|
|
return left.operate(self, right, **kw)
|
|
|
|
|
|
class ColumnOperators(Operators):
|
|
"""Defines boolean, comparison, and other operators for
|
|
:class:`.ColumnElement` expressions.
|
|
|
|
By default, all methods call down to
|
|
:meth:`.operate` or :meth:`.reverse_operate`,
|
|
passing in the appropriate operator function from the
|
|
Python builtin ``operator`` module or
|
|
a SQLAlchemy-specific operator function from
|
|
:mod:`sqlalchemy.expression.operators`. For example
|
|
the ``__eq__`` function::
|
|
|
|
def __eq__(self, other):
|
|
return self.operate(operators.eq, other)
|
|
|
|
Where ``operators.eq`` is essentially::
|
|
|
|
def eq(a, b):
|
|
return a == b
|
|
|
|
The core column expression unit :class:`.ColumnElement`
|
|
overrides :meth:`.Operators.operate` and others
|
|
to return further :class:`.ColumnElement` constructs,
|
|
so that the ``==`` operation above is replaced by a clause
|
|
construct.
|
|
|
|
See also:
|
|
|
|
:ref:`types_operators`
|
|
|
|
:attr:`.TypeEngine.comparator_factory`
|
|
|
|
:class:`.ColumnOperators`
|
|
|
|
:class:`.PropComparator`
|
|
|
|
"""
|
|
|
|
timetuple = None
|
|
"""Hack, allows datetime objects to be compared on the LHS."""
|
|
|
|
def __lt__(self, other):
|
|
"""Implement the ``<`` operator.
|
|
|
|
In a column context, produces the clause ``a < b``.
|
|
|
|
"""
|
|
return self.operate(lt, other)
|
|
|
|
def __le__(self, other):
|
|
"""Implement the ``<=`` operator.
|
|
|
|
In a column context, produces the clause ``a <= b``.
|
|
|
|
"""
|
|
return self.operate(le, other)
|
|
|
|
__hash__ = Operators.__hash__
|
|
|
|
def __eq__(self, other):
|
|
"""Implement the ``==`` operator.
|
|
|
|
In a column context, produces the clause ``a = b``.
|
|
If the target is ``None``, produces ``a IS NULL``.
|
|
|
|
"""
|
|
return self.operate(eq, other)
|
|
|
|
def __ne__(self, other):
|
|
"""Implement the ``!=`` operator.
|
|
|
|
In a column context, produces the clause ``a != b``.
|
|
If the target is ``None``, produces ``a IS NOT NULL``.
|
|
|
|
"""
|
|
return self.operate(ne, other)
|
|
|
|
def __gt__(self, other):
|
|
"""Implement the ``>`` operator.
|
|
|
|
In a column context, produces the clause ``a > b``.
|
|
|
|
"""
|
|
return self.operate(gt, other)
|
|
|
|
def __ge__(self, other):
|
|
"""Implement the ``>=`` operator.
|
|
|
|
In a column context, produces the clause ``a >= b``.
|
|
|
|
"""
|
|
return self.operate(ge, other)
|
|
|
|
def __neg__(self):
|
|
"""Implement the ``-`` operator.
|
|
|
|
In a column context, produces the clause ``-a``.
|
|
|
|
"""
|
|
return self.operate(neg)
|
|
|
|
def __getitem__(self, index):
|
|
"""Implement the [] operator.
|
|
|
|
This can be used by some database-specific types
|
|
such as Postgresql ARRAY and HSTORE.
|
|
|
|
"""
|
|
return self.operate(getitem, index)
|
|
|
|
def __lshift__(self, other):
|
|
"""implement the << operator.
|
|
|
|
Not used by SQLAlchemy core, this is provided
|
|
for custom operator systems which want to use
|
|
<< as an extension point.
|
|
"""
|
|
return self.operate(lshift, other)
|
|
|
|
def __rshift__(self, other):
|
|
"""implement the >> operator.
|
|
|
|
Not used by SQLAlchemy core, this is provided
|
|
for custom operator systems which want to use
|
|
>> as an extension point.
|
|
"""
|
|
return self.operate(rshift, other)
|
|
|
|
def concat(self, other):
|
|
"""Implement the 'concat' operator.
|
|
|
|
In a column context, produces the clause ``a || b``,
|
|
or uses the ``concat()`` operator on MySQL.
|
|
|
|
"""
|
|
return self.operate(concat_op, other)
|
|
|
|
def like(self, other, escape=None):
|
|
"""Implement the ``like`` operator.
|
|
|
|
In a column context, produces the clause ``a LIKE other``.
|
|
|
|
E.g.::
|
|
|
|
select([sometable]).where(sometable.c.column.like("%foobar%"))
|
|
|
|
:param other: expression to be compared
|
|
:param escape: optional escape character, renders the ``ESCAPE``
|
|
keyword, e.g.::
|
|
|
|
somecolumn.like("foo/%bar", escape="/")
|
|
|
|
.. seealso::
|
|
|
|
:meth:`.ColumnOperators.ilike`
|
|
|
|
"""
|
|
return self.operate(like_op, other, escape=escape)
|
|
|
|
def ilike(self, other, escape=None):
|
|
"""Implement the ``ilike`` operator.
|
|
|
|
In a column context, produces the clause ``a ILIKE other``.
|
|
|
|
E.g.::
|
|
|
|
select([sometable]).where(sometable.c.column.ilike("%foobar%"))
|
|
|
|
:param other: expression to be compared
|
|
:param escape: optional escape character, renders the ``ESCAPE``
|
|
keyword, e.g.::
|
|
|
|
somecolumn.ilike("foo/%bar", escape="/")
|
|
|
|
.. seealso::
|
|
|
|
:meth:`.ColumnOperators.like`
|
|
|
|
"""
|
|
return self.operate(ilike_op, other, escape=escape)
|
|
|
|
def in_(self, other):
|
|
"""Implement the ``in`` operator.
|
|
|
|
In a column context, produces the clause ``a IN other``.
|
|
"other" may be a tuple/list of column expressions,
|
|
or a :func:`~.expression.select` construct.
|
|
|
|
"""
|
|
return self.operate(in_op, other)
|
|
|
|
def notin_(self, other):
|
|
"""implement the ``NOT IN`` operator.
|
|
|
|
This is equivalent to using negation with :meth:`.ColumnOperators.in_`,
|
|
i.e. ``~x.in_(y)``.
|
|
|
|
.. versionadded:: 0.8
|
|
|
|
.. seealso::
|
|
|
|
:meth:`.ColumnOperators.in_`
|
|
|
|
"""
|
|
return self.operate(notin_op, other)
|
|
|
|
def notlike(self, other, escape=None):
|
|
"""implement the ``NOT LIKE`` operator.
|
|
|
|
This is equivalent to using negation with
|
|
:meth:`.ColumnOperators.like`, i.e. ``~x.like(y)``.
|
|
|
|
.. versionadded:: 0.8
|
|
|
|
.. seealso::
|
|
|
|
:meth:`.ColumnOperators.like`
|
|
|
|
"""
|
|
return self.operate(notlike_op, other, escape=escape)
|
|
|
|
def notilike(self, other, escape=None):
|
|
"""implement the ``NOT ILIKE`` operator.
|
|
|
|
This is equivalent to using negation with
|
|
:meth:`.ColumnOperators.ilike`, i.e. ``~x.ilike(y)``.
|
|
|
|
.. versionadded:: 0.8
|
|
|
|
.. seealso::
|
|
|
|
:meth:`.ColumnOperators.ilike`
|
|
|
|
"""
|
|
return self.operate(notilike_op, other, escape=escape)
|
|
|
|
def is_(self, other):
|
|
"""Implement the ``IS`` operator.
|
|
|
|
Normally, ``IS`` is generated automatically when comparing to a
|
|
value of ``None``, which resolves to ``NULL``. However, explicit
|
|
usage of ``IS`` may be desirable if comparing to boolean values
|
|
on certain platforms.
|
|
|
|
.. versionadded:: 0.7.9
|
|
|
|
.. seealso:: :meth:`.ColumnOperators.isnot`
|
|
|
|
"""
|
|
return self.operate(is_, other)
|
|
|
|
def isnot(self, other):
|
|
"""Implement the ``IS NOT`` operator.
|
|
|
|
Normally, ``IS NOT`` is generated automatically when comparing to a
|
|
value of ``None``, which resolves to ``NULL``. However, explicit
|
|
usage of ``IS NOT`` may be desirable if comparing to boolean values
|
|
on certain platforms.
|
|
|
|
.. versionadded:: 0.7.9
|
|
|
|
.. seealso:: :meth:`.ColumnOperators.is_`
|
|
|
|
"""
|
|
return self.operate(isnot, other)
|
|
|
|
def startswith(self, other, **kwargs):
|
|
"""Implement the ``startwith`` operator.
|
|
|
|
In a column context, produces the clause ``LIKE '<other>%'``
|
|
|
|
"""
|
|
return self.operate(startswith_op, other, **kwargs)
|
|
|
|
def endswith(self, other, **kwargs):
|
|
"""Implement the 'endswith' operator.
|
|
|
|
In a column context, produces the clause ``LIKE '%<other>'``
|
|
|
|
"""
|
|
return self.operate(endswith_op, other, **kwargs)
|
|
|
|
def contains(self, other, **kwargs):
|
|
"""Implement the 'contains' operator.
|
|
|
|
In a column context, produces the clause ``LIKE '%<other>%'``
|
|
|
|
"""
|
|
return self.operate(contains_op, other, **kwargs)
|
|
|
|
def match(self, other, **kwargs):
|
|
"""Implements the 'match' operator.
|
|
|
|
In a column context, this produces a MATCH clause, i.e.
|
|
``MATCH '<other>'``. The allowed contents of ``other``
|
|
are database backend specific.
|
|
|
|
"""
|
|
return self.operate(match_op, other, **kwargs)
|
|
|
|
def desc(self):
|
|
"""Produce a :func:`~.expression.desc` clause against the
|
|
parent object."""
|
|
return self.operate(desc_op)
|
|
|
|
def asc(self):
|
|
"""Produce a :func:`~.expression.asc` clause against the
|
|
parent object."""
|
|
return self.operate(asc_op)
|
|
|
|
def nullsfirst(self):
|
|
"""Produce a :func:`~.expression.nullsfirst` clause against the
|
|
parent object."""
|
|
return self.operate(nullsfirst_op)
|
|
|
|
def nullslast(self):
|
|
"""Produce a :func:`~.expression.nullslast` clause against the
|
|
parent object."""
|
|
return self.operate(nullslast_op)
|
|
|
|
def collate(self, collation):
|
|
"""Produce a :func:`~.expression.collate` clause against
|
|
the parent object, given the collation string."""
|
|
return self.operate(collate, collation)
|
|
|
|
def __radd__(self, other):
|
|
"""Implement the ``+`` operator in reverse.
|
|
|
|
See :meth:`.ColumnOperators.__add__`.
|
|
|
|
"""
|
|
return self.reverse_operate(add, other)
|
|
|
|
def __rsub__(self, other):
|
|
"""Implement the ``-`` operator in reverse.
|
|
|
|
See :meth:`.ColumnOperators.__sub__`.
|
|
|
|
"""
|
|
return self.reverse_operate(sub, other)
|
|
|
|
def __rmul__(self, other):
|
|
"""Implement the ``*`` operator in reverse.
|
|
|
|
See :meth:`.ColumnOperators.__mul__`.
|
|
|
|
"""
|
|
return self.reverse_operate(mul, other)
|
|
|
|
def __rdiv__(self, other):
|
|
"""Implement the ``/`` operator in reverse.
|
|
|
|
See :meth:`.ColumnOperators.__div__`.
|
|
|
|
"""
|
|
return self.reverse_operate(div, other)
|
|
|
|
def between(self, cleft, cright):
|
|
"""Produce a :func:`~.expression.between` clause against
|
|
the parent object, given the lower and upper range."""
|
|
return self.operate(between_op, cleft, cright)
|
|
|
|
def distinct(self):
|
|
"""Produce a :func:`~.expression.distinct` clause against the
|
|
parent object.
|
|
|
|
"""
|
|
return self.operate(distinct_op)
|
|
|
|
def __add__(self, other):
|
|
"""Implement the ``+`` operator.
|
|
|
|
In a column context, produces the clause ``a + b``
|
|
if the parent object has non-string affinity.
|
|
If the parent object has a string affinity,
|
|
produces the concatenation operator, ``a || b`` -
|
|
see :meth:`.ColumnOperators.concat`.
|
|
|
|
"""
|
|
return self.operate(add, other)
|
|
|
|
def __sub__(self, other):
|
|
"""Implement the ``-`` operator.
|
|
|
|
In a column context, produces the clause ``a - b``.
|
|
|
|
"""
|
|
return self.operate(sub, other)
|
|
|
|
def __mul__(self, other):
|
|
"""Implement the ``*`` operator.
|
|
|
|
In a column context, produces the clause ``a * b``.
|
|
|
|
"""
|
|
return self.operate(mul, other)
|
|
|
|
def __div__(self, other):
|
|
"""Implement the ``/`` operator.
|
|
|
|
In a column context, produces the clause ``a / b``.
|
|
|
|
"""
|
|
return self.operate(div, other)
|
|
|
|
def __mod__(self, other):
|
|
"""Implement the ``%`` operator.
|
|
|
|
In a column context, produces the clause ``a % b``.
|
|
|
|
"""
|
|
return self.operate(mod, other)
|
|
|
|
def __truediv__(self, other):
|
|
"""Implement the ``//`` operator.
|
|
|
|
In a column context, produces the clause ``a / b``.
|
|
|
|
"""
|
|
return self.operate(truediv, other)
|
|
|
|
def __rtruediv__(self, other):
|
|
"""Implement the ``//`` operator in reverse.
|
|
|
|
See :meth:`.ColumnOperators.__truediv__`.
|
|
|
|
"""
|
|
return self.reverse_operate(truediv, other)
|
|
|
|
|
|
def from_():
|
|
raise NotImplementedError()
|
|
|
|
|
|
def as_():
|
|
raise NotImplementedError()
|
|
|
|
|
|
def exists():
|
|
raise NotImplementedError()
|
|
|
|
|
|
def istrue(a):
|
|
raise NotImplementedError()
|
|
|
|
def isfalse(a):
|
|
raise NotImplementedError()
|
|
|
|
def is_(a, b):
|
|
return a.is_(b)
|
|
|
|
|
|
def isnot(a, b):
|
|
return a.isnot(b)
|
|
|
|
|
|
def collate(a, b):
|
|
return a.collate(b)
|
|
|
|
|
|
def op(a, opstring, b):
|
|
return a.op(opstring)(b)
|
|
|
|
|
|
def like_op(a, b, escape=None):
|
|
return a.like(b, escape=escape)
|
|
|
|
|
|
def notlike_op(a, b, escape=None):
|
|
return a.notlike(b, escape=escape)
|
|
|
|
|
|
def ilike_op(a, b, escape=None):
|
|
return a.ilike(b, escape=escape)
|
|
|
|
|
|
def notilike_op(a, b, escape=None):
|
|
return a.notilike(b, escape=escape)
|
|
|
|
|
|
def between_op(a, b, c):
|
|
return a.between(b, c)
|
|
|
|
|
|
def in_op(a, b):
|
|
return a.in_(b)
|
|
|
|
|
|
def notin_op(a, b):
|
|
return a.notin_(b)
|
|
|
|
|
|
def distinct_op(a):
|
|
return a.distinct()
|
|
|
|
|
|
def startswith_op(a, b, escape=None):
|
|
return a.startswith(b, escape=escape)
|
|
|
|
|
|
def notstartswith_op(a, b, escape=None):
|
|
return ~a.startswith(b, escape=escape)
|
|
|
|
|
|
def endswith_op(a, b, escape=None):
|
|
return a.endswith(b, escape=escape)
|
|
|
|
|
|
def notendswith_op(a, b, escape=None):
|
|
return ~a.endswith(b, escape=escape)
|
|
|
|
|
|
def contains_op(a, b, escape=None):
|
|
return a.contains(b, escape=escape)
|
|
|
|
|
|
def notcontains_op(a, b, escape=None):
|
|
return ~a.contains(b, escape=escape)
|
|
|
|
|
|
def match_op(a, b):
|
|
return a.match(b)
|
|
|
|
|
|
def comma_op(a, b):
|
|
raise NotImplementedError()
|
|
|
|
|
|
def concat_op(a, b):
|
|
return a.concat(b)
|
|
|
|
|
|
def desc_op(a):
|
|
return a.desc()
|
|
|
|
|
|
def asc_op(a):
|
|
return a.asc()
|
|
|
|
|
|
def nullsfirst_op(a):
|
|
return a.nullsfirst()
|
|
|
|
|
|
def nullslast_op(a):
|
|
return a.nullslast()
|
|
|
|
|
|
_commutative = set([eq, ne, add, mul])
|
|
|
|
_comparison = set([eq, ne, lt, gt, ge, le, between_op])
|
|
|
|
|
|
def is_comparison(op):
|
|
return op in _comparison or \
|
|
isinstance(op, custom_op) and op.is_comparison
|
|
|
|
|
|
def is_commutative(op):
|
|
return op in _commutative
|
|
|
|
|
|
def is_ordering_modifier(op):
|
|
return op in (asc_op, desc_op,
|
|
nullsfirst_op, nullslast_op)
|
|
|
|
_associative = _commutative.union([concat_op, and_, or_])
|
|
|
|
_natural_self_precedent = _associative.union([getitem])
|
|
"""Operators where if we have (a op b) op c, we don't want to
|
|
parenthesize (a op b).
|
|
|
|
"""
|
|
|
|
_asbool = util.symbol('_asbool', canonical=-10)
|
|
_smallest = util.symbol('_smallest', canonical=-100)
|
|
_largest = util.symbol('_largest', canonical=100)
|
|
|
|
_PRECEDENCE = {
|
|
from_: 15,
|
|
getitem: 15,
|
|
mul: 8,
|
|
truediv: 8,
|
|
div: 8,
|
|
mod: 8,
|
|
neg: 8,
|
|
add: 7,
|
|
sub: 7,
|
|
|
|
concat_op: 6,
|
|
match_op: 6,
|
|
|
|
ilike_op: 6,
|
|
notilike_op: 6,
|
|
like_op: 6,
|
|
notlike_op: 6,
|
|
in_op: 6,
|
|
notin_op: 6,
|
|
|
|
is_: 6,
|
|
isnot: 6,
|
|
|
|
eq: 5,
|
|
ne: 5,
|
|
gt: 5,
|
|
lt: 5,
|
|
ge: 5,
|
|
le: 5,
|
|
|
|
between_op: 5,
|
|
distinct_op: 5,
|
|
inv: 5,
|
|
istrue: 5,
|
|
isfalse: 5,
|
|
and_: 3,
|
|
or_: 2,
|
|
comma_op: -1,
|
|
|
|
desc_op: 3,
|
|
asc_op: 3,
|
|
collate: 4,
|
|
|
|
as_: -1,
|
|
exists: 0,
|
|
_asbool: -10,
|
|
_smallest: _smallest,
|
|
_largest: _largest
|
|
}
|
|
|
|
|
|
def is_precedent(operator, against):
|
|
if operator is against and operator in _natural_self_precedent:
|
|
return False
|
|
else:
|
|
return (_PRECEDENCE.get(operator,
|
|
getattr(operator, 'precedence', _smallest)) <=
|
|
_PRECEDENCE.get(against,
|
|
getattr(against, 'precedence', _largest)))
|