def test_dispatcher():
f = Dispatcher('f')
f.add((int, ), inc)
f.add((float, ), dec)
with warns(DeprecationWarning):
assert f.resolve((int, )) == inc
assert f.dispatch(int) is inc
assert f(1) == 2
assert f(1.0) == 0.0
def test_dispatcher():
f = Dispatcher('f')
f.add((int,), inc)
f.add((float,), dec)
with warns(DeprecationWarning):
assert f.resolve((int,)) == inc
assert f.dispatch(int) is inc
assert f(1) == 2
assert f(1.0) == 0.0
def test_dispatcher():
f = Dispatcher('f')
f.add((int,), inc)
f.add((float,), dec)
with warnings.catch_warnings():
warnings.simplefilter("ignore", DeprecationWarning)
assert f.resolve((int,)) == inc
assert f.dispatch(int) is inc
assert f(1) == 2
assert f(1.0) == 0.0
def test_dispatcher():
f = Dispatcher('f')
f.add((int,), inc)
f.add((float,), dec)
with warnings.catch_warnings():
warnings.simplefilter("ignore", DeprecationWarning)
assert f.resolve((int,)) == inc
assert f.dispatch(int) is inc
assert f(1) == 2
assert f(1.0) == 0.0
def test_source():
def one(x, y):
""" Docstring number one """
return x + y
def two(x, y):
""" Docstring number two """
return x - y
master_doc = 'Doc of the multimethod itself'
f = Dispatcher('f', doc=master_doc)
f.add((int, int), one)
f.add((float, float), two)
assert 'x + y' in f._source(1, 1)
assert 'x - y' in f._source(1.0, 1.0)
def test_source():
def one(x, y):
""" Docstring number one """
return x + y
def two(x, y):
""" Docstring number two """
return x - y
master_doc = 'Doc of the multimethod itself'
f = Dispatcher('f', doc=master_doc)
f.add((int, int), one)
f.add((float, float), two)
assert 'x + y' in f._source(1, 1)
assert 'x - y' in f._source(1.0, 1.0)
def test_ambiguity_register_error_ignore_dup():
f = Dispatcher('f')
class A:
pass
class B(A):
pass
class C(A):
pass
# suppress warning for registering ambiguous signal
f.add((A, B), lambda x,y: None, ambiguity_register_error_ignore_dup)
f.add((B, A), lambda x,y: None, ambiguity_register_error_ignore_dup)
f.add((A, C), lambda x,y: None, ambiguity_register_error_ignore_dup)
f.add((C, A), lambda x,y: None, ambiguity_register_error_ignore_dup)
# raises error if ambiguous signal is passed
assert raises(NotImplementedError, lambda: f(B(), C()))
def test_docstring():
def one(x, y):
""" Docstring number one """
return x + y
def two(x, y):
""" Docstring number two """
return x + y
def three(x, y):
return x + y
master_doc = 'Doc of the multimethod itself'
f = Dispatcher('f', doc=master_doc)
f.add((object, object), one)
f.add((int, int), two)
f.add((float, float), three)
assert one.__doc__.strip() in f.__doc__
assert two.__doc__.strip() in f.__doc__
assert f.__doc__.find(one.__doc__.strip()) < \
f.__doc__.find(two.__doc__.strip())
assert 'object, object' in f.__doc__
assert master_doc in f.__doc__
def test_docstring():
def one(x, y):
""" Docstring number one """
return x + y
def two(x, y):
""" Docstring number two """
return x + y
def three(x, y):
return x + y
master_doc = 'Doc of the multimethod itself'
f = Dispatcher('f', doc=master_doc)
f.add((object, object), one)
f.add((int, int), two)
f.add((float, float), three)
assert one.__doc__.strip() in f.__doc__
assert two.__doc__.strip() in f.__doc__
assert f.__doc__.find(one.__doc__.strip()) < \
f.__doc__.find(two.__doc__.strip())
assert 'object, object' in f.__doc__
assert master_doc in f.__doc__
def test_halt_method_resolution():
g = [0]
def on_ambiguity(a, b):
g[0] += 1
f = Dispatcher('f')
halt_ordering()
def func(*args):
pass
f.add((int, object), func)
f.add((object, int), func)
assert g == [0]
restart_ordering(on_ambiguity=on_ambiguity)
assert g == [1]
assert set(f.ordering) == {(int, object), (object, int)}
def test_halt_method_resolution():
g = [0]
def on_ambiguity(a, b):
g[0] += 1
f = Dispatcher('f')
halt_ordering()
def func(*args):
pass
f.add((int, object), func)
f.add((object, int), func)
assert g == [0]
restart_ordering(on_ambiguity=on_ambiguity)
assert g == [1]
assert set(f.ordering) == set([(int, object), (object, int)])
def test_on_ambiguity():
f = Dispatcher('f')
def identity(x): return x
ambiguities = [False]
def on_ambiguity(dispatcher, amb):
ambiguities[0] = True
f.add((object, object), identity, on_ambiguity=on_ambiguity)
assert not ambiguities[0]
f.add((object, float), identity, on_ambiguity=on_ambiguity)
assert not ambiguities[0]
f.add((float, object), identity, on_ambiguity=on_ambiguity)
assert ambiguities[0]
def test_on_ambiguity():
f = Dispatcher('f')
def identity(x): return x
ambiguities = [False]
def on_ambiguity(dispatcher, amb):
ambiguities[0] = True
f.add((object, object), identity, on_ambiguity=on_ambiguity)
assert not ambiguities[0]
f.add((object, float), identity, on_ambiguity=on_ambiguity)
assert not ambiguities[0]
f.add((float, object), identity, on_ambiguity=on_ambiguity)
assert ambiguities[0]
def test_help():
def one(x, y):
""" Docstring number one """
return x + y
def two(x, y):
""" Docstring number two """
return x + y
def three(x, y):
""" Docstring number three """
return x + y
master_doc = 'Doc of the multimethod itself'
f = Dispatcher('f', doc=master_doc)
f.add((object, object), one)
f.add((int, int), two)
f.add((float, float), three)
assert f._help(1, 1) == two.__doc__
assert f._help(1.0, 2.0) == three.__doc__
def test_help():
def one(x, y):
""" Docstring number one """
return x + y
def two(x, y):
""" Docstring number two """
return x + y
def three(x, y):
""" Docstring number three """
return x + y
master_doc = 'Doc of the multimethod itself'
f = Dispatcher('f', doc=master_doc)
f.add((object, object), one)
f.add((int, int), two)
f.add((float, float), three)
assert f._help(1, 1) == two.__doc__
assert f._help(1.0, 2.0) == three.__doc__
def test_raise_error_on_non_class():
f = Dispatcher('f')
assert raises(TypeError, lambda: f.add((1, ), inc))
class AssocOpDispatcher:
"""
Handler dispatcher for associative operators
.. notes::
This approach is experimental, and can be replaced or deleted in the future.
See https://github.com/sympy/sympy/pull/19463.
Explanation
===========
If arguments of different types are passed, the classes which handle the operation for each type
are collected. Then, a class which performs the operation is selected by recursive binary dispatching.
Dispatching relation can be registered by ``register_handlerclass`` method.
Priority registration is unordered. You cannot make ``A*B`` and ``B*A`` refer to
different handler classes. All logic dealing with the order of arguments must be implemented
in the handler class.
Examples
========
>>> from sympy import Add, Expr, Symbol
>>> from sympy.core.add import add
>>> class NewExpr(Expr):
... @property
... def _add_handler(self):
... return NewAdd
>>> class NewAdd(NewExpr, Add):
... pass
>>> add.register_handlerclass((Add, NewAdd), NewAdd)
>>> a, b = Symbol('a'), NewExpr()
>>> add(a, b) == NewAdd(a, b)
True
"""
def __init__(self, name, doc=None):
self.name = name
self.doc = doc
self.handlerattr = "_%s_handler" % name
self._handlergetter = attrgetter(self.handlerattr)
self._dispatcher = Dispatcher(name)
def __repr__(self):
return "<dispatched %s>" % self.name
def register_handlerclass(
self,
classes,
typ,
on_ambiguity=ambiguity_register_error_ignore_dup):
"""
Register the handler class for two classes, in both straight and reversed order.
Paramteters
===========
classes : tuple of two types
Classes who are compared with each other.
typ:
Class which is registered to represent *cls1* and *cls2*.
Handler method of *self* must be implemented in this class.
"""
if not len(classes) == 2:
raise RuntimeError(
"Only binary dispatch is supported, but got %s types: <%s>." %
(len(classes), str_signature(classes)))
if len(set(classes)) == 1:
raise RuntimeError("Duplicate types <%s> cannot be dispatched." %
str_signature(classes))
self._dispatcher.add(tuple(classes), typ, on_ambiguity=on_ambiguity)
self._dispatcher.add(tuple(reversed(classes)),
typ,
on_ambiguity=on_ambiguity)
@cacheit
def __call__(self, *args, _sympify=True, **kwargs):
"""
Parameters
==========
*args :
Arguments which are operated
"""
if _sympify:
args = tuple(map(_sympify_, args))
handlers = frozenset(map(self._handlergetter, args))
# no need to sympify again
return self.dispatch(handlers)(*args, _sympify=False, **kwargs)
@cacheit
def dispatch(self, handlers):
"""
Select the handler class, and return its handler method.
"""
# Quick exit for the case where all handlers are same
if len(handlers) == 1:
h, = handlers
if not isinstance(h, type):
raise RuntimeError("Handler {!r} is not a type.".format(h))
return h
# Recursively select with registered binary priority
for i, typ in enumerate(handlers):
if not isinstance(typ, type):
raise RuntimeError("Handler {!r} is not a type.".format(typ))
if i == 0:
handler = typ
else:
prev_handler = handler
handler = self._dispatcher.dispatch(prev_handler, typ)
if not isinstance(handler, type):
raise RuntimeError(
"Dispatcher for {!r} and {!r} must return a type, but got {!r}"
.format(prev_handler, typ, handler))
# return handler class
return handler
@property
def __doc__(self):
docs = [
"Multiply dispatched associative operator: %s" % self.name,
"Note that support for this is experimental, see the docs for :class:`AssocOpDispatcher` for details"
]
if self.doc:
docs.append(self.doc)
s = "Registered handler classes\n"
s += '=' * len(s)
docs.append(s)
amb_sigs = []
typ_sigs = defaultdict(list)
for sigs in self._dispatcher.ordering[::-1]:
key = self._dispatcher.funcs[sigs]
typ_sigs[key].append(sigs)
for typ, sigs in typ_sigs.items():
sigs_str = ', '.join('<%s>' % str_signature(sig) for sig in sigs)
if isinstance(typ, RaiseNotImplementedError):
amb_sigs.append(sigs_str)
continue
s = 'Inputs: %s\n' % sigs_str
s += '-' * len(s) + '\n'
s += typ.__name__
docs.append(s)
if amb_sigs:
s = "Ambiguous handler classes\n"
s += '=' * len(s)
docs.append(s)
s = '\n'.join(amb_sigs)
docs.append(s)
return '\n\n'.join(docs)
class KindDispatcher:
"""
Dispatcher to select a kind from multiple kinds by binary dispatching.
.. notes::
This approach is experimental, and can be replaced or deleted in
the future.
Explanation
===========
SymPy object's :obj:`sympy.core.kind.Kind()` vaguely represents the
algebraic structure where the object belongs to. Therefore, with
given operation, we can always find a dominating kind among the
different kinds. This class selects the kind by recursive binary
dispatching. If the result cannot be determined, ``UndefinedKind``
is returned.
Examples
========
Multiplication between numbers return number.
>>> from sympy import NumberKind, Mul
>>> Mul._kind_dispatcher(NumberKind, NumberKind)
NumberKind
Multiplication between number and unknown-kind object returns unknown kind.
>>> from sympy import UndefinedKind
>>> Mul._kind_dispatcher(NumberKind, UndefinedKind)
UndefinedKind
Any number and order of kinds is allowed.
>>> Mul._kind_dispatcher(UndefinedKind, NumberKind)
UndefinedKind
>>> Mul._kind_dispatcher(NumberKind, UndefinedKind, NumberKind)
UndefinedKind
Since matrix forms a vector space over scalar field, multiplication
between matrix with numeric element and number returns matrix with
numeric element.
>>> from sympy.matrices import MatrixKind
>>> Mul._kind_dispatcher(MatrixKind(NumberKind), NumberKind)
MatrixKind(NumberKind)
If a matrix with number element and another matrix with unknown-kind
element are multiplied, we know that the result is matrix but the
kind of its elements is unknown.
>>> Mul._kind_dispatcher(MatrixKind(NumberKind), MatrixKind(UndefinedKind))
MatrixKind(UndefinedKind)
Parameters
==========
name : str
commutative : bool, optional
If True, binary dispatch will be automatically registered in
reversed order as well.
doc : str, optional
"""
def __init__(self, name, commutative=False, doc=None):
self.name = name
self.doc = doc
self.commutative = commutative
self._dispatcher = Dispatcher(name)
def __repr__(self):
return "<dispatched %s>" % self.name
def register(self, *types, **kwargs):
"""
Register the binary dispatcher for two kind classes.
If *self.commutative* is ``True``, signature in reversed order is
automatically registered as well.
"""
on_ambiguity = kwargs.pop("on_ambiguity", None)
if not on_ambiguity:
if self.commutative:
on_ambiguity = ambiguity_register_error_ignore_dup
else:
on_ambiguity = ambiguity_warn
kwargs.update(on_ambiguity=on_ambiguity)
if not len(types) == 2:
raise RuntimeError(
"Only binary dispatch is supported, but got %s types: <%s>." % (
len(types), str_signature(types)
))
def _(func):
self._dispatcher.add(types, func, **kwargs)
if self.commutative:
self._dispatcher.add(tuple(reversed(types)), func, **kwargs)
return _
def __call__(self, *args, **kwargs):
if self.commutative:
kinds = frozenset(args)
else:
kinds = []
prev = None
for a in args:
if prev is not a:
kinds.append(a)
prev = a
return self.dispatch_kinds(kinds, **kwargs)
@cacheit
def dispatch_kinds(self, kinds, **kwargs):
# Quick exit for the case where all kinds are same
if len(kinds) == 1:
result, = kinds
if not isinstance(result, Kind):
raise RuntimeError("%s is not a kind." % result)
return result
for i,kind in enumerate(kinds):
if not isinstance(kind, Kind):
raise RuntimeError("%s is not a kind." % kind)
if i == 0:
result = kind
else:
prev_kind = result
t1, t2 = type(prev_kind), type(kind)
k1, k2 = prev_kind, kind
func = self._dispatcher.dispatch(t1, t2)
if func is None and self.commutative:
# try reversed order
func = self._dispatcher.dispatch(t2, t1)
k1, k2 = k2, k1
if func is None:
# unregistered kind relation
result = UndefinedKind
else:
result = func(k1, k2)
if not isinstance(result, Kind):
raise RuntimeError(
"Dispatcher for {!r} and {!r} must return a Kind, but got {!r}".format(
prev_kind, kind, result
))
return result
@property
def __doc__(self):
docs = [
"Kind dispatcher : %s" % self.name,
"Note that support for this is experimental. See the docs for :class:`KindDispatcher` for details"
]
if self.doc:
docs.append(self.doc)
s = "Registered kind classes\n"
s += '=' * len(s)
docs.append(s)
amb_sigs = []
typ_sigs = defaultdict(list)
for sigs in self._dispatcher.ordering[::-1]:
key = self._dispatcher.funcs[sigs]
typ_sigs[key].append(sigs)
for func, sigs in typ_sigs.items():
sigs_str = ', '.join('<%s>' % str_signature(sig) for sig in sigs)
if isinstance(func, RaiseNotImplementedError):
amb_sigs.append(sigs_str)
continue
s = 'Inputs: %s\n' % sigs_str
s += '-' * len(s) + '\n'
if func.__doc__:
s += func.__doc__.strip()
else:
s += func.__name__
docs.append(s)
if amb_sigs:
s = "Ambiguous kind classes\n"
s += '=' * len(s)
docs.append(s)
s = '\n'.join(amb_sigs)
docs.append(s)
return '\n\n'.join(docs)
def test_raise_error_on_non_class():
f = Dispatcher('f')
assert raises(TypeError, lambda: f.add((1,), inc))
