mirror of
https://github.com/python/cpython.git
synced 2024-11-23 09:54:58 +08:00
476 lines
11 KiB
Python
476 lines
11 KiB
Python
"""
|
|
Operator Interface
|
|
|
|
This module exports a set of functions corresponding to the intrinsic
|
|
operators of Python. For example, operator.add(x, y) is equivalent
|
|
to the expression x+y. The function names are those used for special
|
|
methods; variants without leading and trailing '__' are also provided
|
|
for convenience.
|
|
|
|
This is the pure Python implementation of the module.
|
|
"""
|
|
|
|
__all__ = ['abs', 'add', 'and_', 'attrgetter', 'call', 'concat', 'contains', 'countOf',
|
|
'delitem', 'eq', 'floordiv', 'ge', 'getitem', 'gt', 'iadd', 'iand',
|
|
'iconcat', 'ifloordiv', 'ilshift', 'imatmul', 'imod', 'imul',
|
|
'index', 'indexOf', 'inv', 'invert', 'ior', 'ipow', 'irshift',
|
|
'is_', 'is_none', 'is_not', 'is_not_none', 'isub', 'itemgetter', 'itruediv',
|
|
'ixor', 'le', 'length_hint', 'lshift', 'lt', 'matmul', 'methodcaller', 'mod',
|
|
'mul', 'ne', 'neg', 'not_', 'or_', 'pos', 'pow', 'rshift',
|
|
'setitem', 'sub', 'truediv', 'truth', 'xor']
|
|
|
|
from builtins import abs as _abs
|
|
|
|
|
|
# Comparison Operations *******************************************************#
|
|
|
|
def lt(a, b):
|
|
"Same as a < b."
|
|
return a < b
|
|
|
|
def le(a, b):
|
|
"Same as a <= b."
|
|
return a <= b
|
|
|
|
def eq(a, b):
|
|
"Same as a == b."
|
|
return a == b
|
|
|
|
def ne(a, b):
|
|
"Same as a != b."
|
|
return a != b
|
|
|
|
def ge(a, b):
|
|
"Same as a >= b."
|
|
return a >= b
|
|
|
|
def gt(a, b):
|
|
"Same as a > b."
|
|
return a > b
|
|
|
|
# Logical Operations **********************************************************#
|
|
|
|
def not_(a):
|
|
"Same as not a."
|
|
return not a
|
|
|
|
def truth(a):
|
|
"Return True if a is true, False otherwise."
|
|
return True if a else False
|
|
|
|
def is_(a, b):
|
|
"Same as a is b."
|
|
return a is b
|
|
|
|
def is_not(a, b):
|
|
"Same as a is not b."
|
|
return a is not b
|
|
|
|
def is_none(a):
|
|
"Same as a is None."
|
|
return a is None
|
|
|
|
def is_not_none(a):
|
|
"Same as a is not None."
|
|
return a is not None
|
|
|
|
# Mathematical/Bitwise Operations *********************************************#
|
|
|
|
def abs(a):
|
|
"Same as abs(a)."
|
|
return _abs(a)
|
|
|
|
def add(a, b):
|
|
"Same as a + b."
|
|
return a + b
|
|
|
|
def and_(a, b):
|
|
"Same as a & b."
|
|
return a & b
|
|
|
|
def floordiv(a, b):
|
|
"Same as a // b."
|
|
return a // b
|
|
|
|
def index(a):
|
|
"Same as a.__index__()."
|
|
return a.__index__()
|
|
|
|
def inv(a):
|
|
"Same as ~a."
|
|
return ~a
|
|
invert = inv
|
|
|
|
def lshift(a, b):
|
|
"Same as a << b."
|
|
return a << b
|
|
|
|
def mod(a, b):
|
|
"Same as a % b."
|
|
return a % b
|
|
|
|
def mul(a, b):
|
|
"Same as a * b."
|
|
return a * b
|
|
|
|
def matmul(a, b):
|
|
"Same as a @ b."
|
|
return a @ b
|
|
|
|
def neg(a):
|
|
"Same as -a."
|
|
return -a
|
|
|
|
def or_(a, b):
|
|
"Same as a | b."
|
|
return a | b
|
|
|
|
def pos(a):
|
|
"Same as +a."
|
|
return +a
|
|
|
|
def pow(a, b):
|
|
"Same as a ** b."
|
|
return a ** b
|
|
|
|
def rshift(a, b):
|
|
"Same as a >> b."
|
|
return a >> b
|
|
|
|
def sub(a, b):
|
|
"Same as a - b."
|
|
return a - b
|
|
|
|
def truediv(a, b):
|
|
"Same as a / b."
|
|
return a / b
|
|
|
|
def xor(a, b):
|
|
"Same as a ^ b."
|
|
return a ^ b
|
|
|
|
# Sequence Operations *********************************************************#
|
|
|
|
def concat(a, b):
|
|
"Same as a + b, for a and b sequences."
|
|
if not hasattr(a, '__getitem__'):
|
|
msg = "'%s' object can't be concatenated" % type(a).__name__
|
|
raise TypeError(msg)
|
|
return a + b
|
|
|
|
def contains(a, b):
|
|
"Same as b in a (note reversed operands)."
|
|
return b in a
|
|
|
|
def countOf(a, b):
|
|
"Return the number of items in a which are, or which equal, b."
|
|
count = 0
|
|
for i in a:
|
|
if i is b or i == b:
|
|
count += 1
|
|
return count
|
|
|
|
def delitem(a, b):
|
|
"Same as del a[b]."
|
|
del a[b]
|
|
|
|
def getitem(a, b):
|
|
"Same as a[b]."
|
|
return a[b]
|
|
|
|
def indexOf(a, b):
|
|
"Return the first index of b in a."
|
|
for i, j in enumerate(a):
|
|
if j is b or j == b:
|
|
return i
|
|
else:
|
|
raise ValueError('sequence.index(x): x not in sequence')
|
|
|
|
def setitem(a, b, c):
|
|
"Same as a[b] = c."
|
|
a[b] = c
|
|
|
|
def length_hint(obj, default=0):
|
|
"""
|
|
Return an estimate of the number of items in obj.
|
|
This is useful for presizing containers when building from an iterable.
|
|
|
|
If the object supports len(), the result will be exact. Otherwise, it may
|
|
over- or under-estimate by an arbitrary amount. The result will be an
|
|
integer >= 0.
|
|
"""
|
|
if not isinstance(default, int):
|
|
msg = ("'%s' object cannot be interpreted as an integer" %
|
|
type(default).__name__)
|
|
raise TypeError(msg)
|
|
|
|
try:
|
|
return len(obj)
|
|
except TypeError:
|
|
pass
|
|
|
|
try:
|
|
hint = type(obj).__length_hint__
|
|
except AttributeError:
|
|
return default
|
|
|
|
try:
|
|
val = hint(obj)
|
|
except TypeError:
|
|
return default
|
|
if val is NotImplemented:
|
|
return default
|
|
if not isinstance(val, int):
|
|
msg = ('__length_hint__ must be integer, not %s' %
|
|
type(val).__name__)
|
|
raise TypeError(msg)
|
|
if val < 0:
|
|
msg = '__length_hint__() should return >= 0'
|
|
raise ValueError(msg)
|
|
return val
|
|
|
|
# Other Operations ************************************************************#
|
|
|
|
def call(obj, /, *args, **kwargs):
|
|
"""Same as obj(*args, **kwargs)."""
|
|
return obj(*args, **kwargs)
|
|
|
|
# Generalized Lookup Objects **************************************************#
|
|
|
|
class attrgetter:
|
|
"""
|
|
Return a callable object that fetches the given attribute(s) from its operand.
|
|
After f = attrgetter('name'), the call f(r) returns r.name.
|
|
After g = attrgetter('name', 'date'), the call g(r) returns (r.name, r.date).
|
|
After h = attrgetter('name.first', 'name.last'), the call h(r) returns
|
|
(r.name.first, r.name.last).
|
|
"""
|
|
__slots__ = ('_attrs', '_call')
|
|
|
|
def __init__(self, attr, /, *attrs):
|
|
if not attrs:
|
|
if not isinstance(attr, str):
|
|
raise TypeError('attribute name must be a string')
|
|
self._attrs = (attr,)
|
|
names = attr.split('.')
|
|
def func(obj):
|
|
for name in names:
|
|
obj = getattr(obj, name)
|
|
return obj
|
|
self._call = func
|
|
else:
|
|
self._attrs = (attr,) + attrs
|
|
getters = tuple(map(attrgetter, self._attrs))
|
|
def func(obj):
|
|
return tuple(getter(obj) for getter in getters)
|
|
self._call = func
|
|
|
|
def __call__(self, obj, /):
|
|
return self._call(obj)
|
|
|
|
def __repr__(self):
|
|
return '%s.%s(%s)' % (self.__class__.__module__,
|
|
self.__class__.__qualname__,
|
|
', '.join(map(repr, self._attrs)))
|
|
|
|
def __reduce__(self):
|
|
return self.__class__, self._attrs
|
|
|
|
class itemgetter:
|
|
"""
|
|
Return a callable object that fetches the given item(s) from its operand.
|
|
After f = itemgetter(2), the call f(r) returns r[2].
|
|
After g = itemgetter(2, 5, 3), the call g(r) returns (r[2], r[5], r[3])
|
|
"""
|
|
__slots__ = ('_items', '_call')
|
|
|
|
def __init__(self, item, /, *items):
|
|
if not items:
|
|
self._items = (item,)
|
|
def func(obj):
|
|
return obj[item]
|
|
self._call = func
|
|
else:
|
|
self._items = items = (item,) + items
|
|
def func(obj):
|
|
return tuple(obj[i] for i in items)
|
|
self._call = func
|
|
|
|
def __call__(self, obj, /):
|
|
return self._call(obj)
|
|
|
|
def __repr__(self):
|
|
return '%s.%s(%s)' % (self.__class__.__module__,
|
|
self.__class__.__name__,
|
|
', '.join(map(repr, self._items)))
|
|
|
|
def __reduce__(self):
|
|
return self.__class__, self._items
|
|
|
|
class methodcaller:
|
|
"""
|
|
Return a callable object that calls the given method on its operand.
|
|
After f = methodcaller('name'), the call f(r) returns r.name().
|
|
After g = methodcaller('name', 'date', foo=1), the call g(r) returns
|
|
r.name('date', foo=1).
|
|
"""
|
|
__slots__ = ('_name', '_args', '_kwargs')
|
|
|
|
def __init__(self, name, /, *args, **kwargs):
|
|
self._name = name
|
|
if not isinstance(self._name, str):
|
|
raise TypeError('method name must be a string')
|
|
self._args = args
|
|
self._kwargs = kwargs
|
|
|
|
def __call__(self, obj, /):
|
|
return getattr(obj, self._name)(*self._args, **self._kwargs)
|
|
|
|
def __repr__(self):
|
|
args = [repr(self._name)]
|
|
args.extend(map(repr, self._args))
|
|
args.extend('%s=%r' % (k, v) for k, v in self._kwargs.items())
|
|
return '%s.%s(%s)' % (self.__class__.__module__,
|
|
self.__class__.__name__,
|
|
', '.join(args))
|
|
|
|
def __reduce__(self):
|
|
if not self._kwargs:
|
|
return self.__class__, (self._name,) + self._args
|
|
else:
|
|
from functools import partial
|
|
return partial(self.__class__, self._name, **self._kwargs), self._args
|
|
|
|
|
|
# In-place Operations *********************************************************#
|
|
|
|
def iadd(a, b):
|
|
"Same as a += b."
|
|
a += b
|
|
return a
|
|
|
|
def iand(a, b):
|
|
"Same as a &= b."
|
|
a &= b
|
|
return a
|
|
|
|
def iconcat(a, b):
|
|
"Same as a += b, for a and b sequences."
|
|
if not hasattr(a, '__getitem__'):
|
|
msg = "'%s' object can't be concatenated" % type(a).__name__
|
|
raise TypeError(msg)
|
|
a += b
|
|
return a
|
|
|
|
def ifloordiv(a, b):
|
|
"Same as a //= b."
|
|
a //= b
|
|
return a
|
|
|
|
def ilshift(a, b):
|
|
"Same as a <<= b."
|
|
a <<= b
|
|
return a
|
|
|
|
def imod(a, b):
|
|
"Same as a %= b."
|
|
a %= b
|
|
return a
|
|
|
|
def imul(a, b):
|
|
"Same as a *= b."
|
|
a *= b
|
|
return a
|
|
|
|
def imatmul(a, b):
|
|
"Same as a @= b."
|
|
a @= b
|
|
return a
|
|
|
|
def ior(a, b):
|
|
"Same as a |= b."
|
|
a |= b
|
|
return a
|
|
|
|
def ipow(a, b):
|
|
"Same as a **= b."
|
|
a **=b
|
|
return a
|
|
|
|
def irshift(a, b):
|
|
"Same as a >>= b."
|
|
a >>= b
|
|
return a
|
|
|
|
def isub(a, b):
|
|
"Same as a -= b."
|
|
a -= b
|
|
return a
|
|
|
|
def itruediv(a, b):
|
|
"Same as a /= b."
|
|
a /= b
|
|
return a
|
|
|
|
def ixor(a, b):
|
|
"Same as a ^= b."
|
|
a ^= b
|
|
return a
|
|
|
|
|
|
try:
|
|
from _operator import *
|
|
except ImportError:
|
|
pass
|
|
else:
|
|
from _operator import __doc__ # noqa: F401
|
|
|
|
# All of these "__func__ = func" assignments have to happen after importing
|
|
# from _operator to make sure they're set to the right function
|
|
__lt__ = lt
|
|
__le__ = le
|
|
__eq__ = eq
|
|
__ne__ = ne
|
|
__ge__ = ge
|
|
__gt__ = gt
|
|
__not__ = not_
|
|
__abs__ = abs
|
|
__add__ = add
|
|
__and__ = and_
|
|
__call__ = call
|
|
__floordiv__ = floordiv
|
|
__index__ = index
|
|
__inv__ = inv
|
|
__invert__ = invert
|
|
__lshift__ = lshift
|
|
__mod__ = mod
|
|
__mul__ = mul
|
|
__matmul__ = matmul
|
|
__neg__ = neg
|
|
__or__ = or_
|
|
__pos__ = pos
|
|
__pow__ = pow
|
|
__rshift__ = rshift
|
|
__sub__ = sub
|
|
__truediv__ = truediv
|
|
__xor__ = xor
|
|
__concat__ = concat
|
|
__contains__ = contains
|
|
__delitem__ = delitem
|
|
__getitem__ = getitem
|
|
__setitem__ = setitem
|
|
__iadd__ = iadd
|
|
__iand__ = iand
|
|
__iconcat__ = iconcat
|
|
__ifloordiv__ = ifloordiv
|
|
__ilshift__ = ilshift
|
|
__imod__ = imod
|
|
__imul__ = imul
|
|
__imatmul__ = imatmul
|
|
__ior__ = ior
|
|
__ipow__ = ipow
|
|
__irshift__ = irshift
|
|
__isub__ = isub
|
|
__itruediv__ = itruediv
|
|
__ixor__ = ixor
|