LSST Applications  21.0.0+04719a4bac,21.0.0-1-ga51b5d4+f5e6047307,21.0.0-11-g2b59f77+a9c1acf22d,21.0.0-11-ga42c5b2+86977b0b17,21.0.0-12-gf4ce030+76814010d2,21.0.0-13-g1721dae+760e7a6536,21.0.0-13-g3a573fe+768d78a30a,21.0.0-15-g5a7caf0+f21cbc5713,21.0.0-16-g0fb55c1+b60e2d390c,21.0.0-19-g4cded4ca+71a93a33c0,21.0.0-2-g103fe59+bb20972958,21.0.0-2-g45278ab+04719a4bac,21.0.0-2-g5242d73+3ad5d60fb1,21.0.0-2-g7f82c8f+8babb168e8,21.0.0-2-g8f08a60+06509c8b61,21.0.0-2-g8faa9b5+616205b9df,21.0.0-2-ga326454+8babb168e8,21.0.0-2-gde069b7+5e4aea9c2f,21.0.0-2-gecfae73+1d3a86e577,21.0.0-2-gfc62afb+3ad5d60fb1,21.0.0-25-g1d57be3cd+e73869a214,21.0.0-3-g357aad2+ed88757d29,21.0.0-3-g4a4ce7f+3ad5d60fb1,21.0.0-3-g4be5c26+3ad5d60fb1,21.0.0-3-g65f322c+e0b24896a3,21.0.0-3-g7d9da8d+616205b9df,21.0.0-3-ge02ed75+a9c1acf22d,21.0.0-4-g591bb35+a9c1acf22d,21.0.0-4-g65b4814+b60e2d390c,21.0.0-4-gccdca77+0de219a2bc,21.0.0-4-ge8a399c+6c55c39e83,21.0.0-5-gd00fb1e+05fce91b99,21.0.0-6-gc675373+3ad5d60fb1,21.0.0-64-g1122c245+4fb2b8f86e,21.0.0-7-g04766d7+cd19d05db2,21.0.0-7-gdf92d54+04719a4bac,21.0.0-8-g5674e7b+d1bd76f71f,master-gac4afde19b+a9c1acf22d,w.2021.13
LSST Data Management Base Package
Classes | Functions | Variables
lsst.utils.wrappers Namespace Reference

Classes

class  TemplateMeta
 

Functions

def isAttributeSafeToTransfer (name, value)
 
def continueClass (cls)
 
def inClass (cls, name=None)
 

Variables

 INTRINSIC_SPECIAL_ATTRIBUTES
 

Function Documentation

◆ continueClass()

def lsst.utils.wrappers.continueClass (   cls)
Re-open the decorated class, adding any new definitions into the original.

For example:

.. code-block:: python

    class Foo:
        pass

    @continueClass
    class Foo:
        def run(self):
            return None

is equivalent to:

.. code-block:: python

    class Foo:
        def run(self):
            return None

.. warning::

    Python's built-in `super` function does not behave properly in classes
    decorated with `continueClass`.  Base class methods must be invoked
    directly using their explicit types instead.

Definition at line 59 of file wrappers.py.

59 def continueClass(cls):
60  """Re-open the decorated class, adding any new definitions into the original.
61 
62  For example:
63 
64  .. code-block:: python
65 
66  class Foo:
67  pass
68 
69  @continueClass
70  class Foo:
71  def run(self):
72  return None
73 
74  is equivalent to:
75 
76  .. code-block:: python
77 
78  class Foo:
79  def run(self):
80  return None
81 
82  .. warning::
83 
84  Python's built-in `super` function does not behave properly in classes
85  decorated with `continueClass`. Base class methods must be invoked
86  directly using their explicit types instead.
87 
88  """
89  orig = getattr(sys.modules[cls.__module__], cls.__name__)
90  for name in dir(cls):
91  # Common descriptors like classmethod and staticmethod can only be
92  # accessed without invoking their magic if we use __dict__; if we use
93  # getattr on those we'll get e.g. a bound method instance on the dummy
94  # class rather than a classmethod instance we can put on the target
95  # class.
96  attr = cls.__dict__.get(name, None) or getattr(cls, name)
97  if isAttributeSafeToTransfer(name, attr):
98  setattr(orig, name, attr)
99  return orig
100 
101 
def continueClass(cls)
Definition: wrappers.py:59
def isAttributeSafeToTransfer(name, value)
Definition: wrappers.py:45

◆ inClass()

def lsst.utils.wrappers.inClass (   cls,
  name = None 
)
Add the decorated function to the given class as a method.

For example:

.. code-block:: python

    class Foo:
        pass

    @inClass(Foo)
    def run(self):
        return None

is equivalent to:

.. code-block:: python

    class Foo:
        def run(self):
            return None

Standard decorators like ``classmethod``, ``staticmethod``, and
``property`` may be used *after* this decorator.  Custom decorators
may only be used if they return an object with a ``__name__`` attribute
or the ``name`` optional argument is provided.

Definition at line 102 of file wrappers.py.

102 def inClass(cls, name=None):
103  """Add the decorated function to the given class as a method.
104 
105  For example:
106 
107  .. code-block:: python
108 
109  class Foo:
110  pass
111 
112  @inClass(Foo)
113  def run(self):
114  return None
115 
116  is equivalent to:
117 
118  .. code-block:: python
119 
120  class Foo:
121  def run(self):
122  return None
123 
124  Standard decorators like ``classmethod``, ``staticmethod``, and
125  ``property`` may be used *after* this decorator. Custom decorators
126  may only be used if they return an object with a ``__name__`` attribute
127  or the ``name`` optional argument is provided.
128  """
129  def decorate(func):
130  # Using 'name' instead of 'name1' breaks the closure because
131  # assignment signals a strictly local variable.
132  name1 = name
133  if name1 is None:
134  if hasattr(func, "__name__"):
135  name1 = func.__name__
136  else:
137  if hasattr(func, "__func__"):
138  # classmethod and staticmethod have __func__ but no __name__
139  name1 = func.__func__.__name__
140  elif hasattr(func, "fget"):
141  # property has fget but no __name__
142  name1 = func.fget.__name__
143  else:
144  raise ValueError(
145  "Could not guess attribute name for '{}'.".format(func)
146  )
147  setattr(cls, name1, func)
148  return func
149  return decorate
150 
151 
def format(config, name=None, writeSourceLine=True, prefix="", verbose=False)
Definition: history.py:174
def inClass(cls, name=None)
Definition: wrappers.py:102

◆ isAttributeSafeToTransfer()

def lsst.utils.wrappers.isAttributeSafeToTransfer (   name,
  value 
)
Return True if an attribute is safe to monkeypatch-transfer to another
class.

This rejects special methods that are defined automatically for all
classes, leaving only those explicitly defined in a class decorated by
`continueClass` or registered with an instance of `TemplateMeta`.

Definition at line 45 of file wrappers.py.

45 def isAttributeSafeToTransfer(name, value):
46  """Return True if an attribute is safe to monkeypatch-transfer to another
47  class.
48 
49  This rejects special methods that are defined automatically for all
50  classes, leaving only those explicitly defined in a class decorated by
51  `continueClass` or registered with an instance of `TemplateMeta`.
52  """
53  if name.startswith("__") and (value is getattr(object, name, None)
54  or name in INTRINSIC_SPECIAL_ATTRIBUTES):
55  return False
56  return True
57 
58 

Variable Documentation

◆ INTRINSIC_SPECIAL_ATTRIBUTES

lsst.utils.wrappers.INTRINSIC_SPECIAL_ATTRIBUTES
Initial value:
1 = frozenset((
2  "__qualname__",
3  "__module__",
4  "__metaclass__",
5  "__dict__",
6  "__weakref__",
7  "__class__",
8  "__subclasshook__",
9  "__name__",
10  "__doc__",
11 ))

Definition at line 32 of file wrappers.py.