LSSTApplications  18.0.0+106,18.0.0+50,19.0.0,19.0.0+1,19.0.0+10,19.0.0+11,19.0.0+13,19.0.0+17,19.0.0+2,19.0.0-1-g20d9b18+6,19.0.0-1-g425ff20,19.0.0-1-g5549ca4,19.0.0-1-g580fafe+6,19.0.0-1-g6fe20d0+1,19.0.0-1-g7011481+9,19.0.0-1-g8c57eb9+6,19.0.0-1-gb5175dc+11,19.0.0-1-gdc0e4a7+9,19.0.0-1-ge272bc4+6,19.0.0-1-ge3aa853,19.0.0-10-g448f008b,19.0.0-12-g6990b2c,19.0.0-2-g0d9f9cd+11,19.0.0-2-g3d9e4fb2+11,19.0.0-2-g5037de4,19.0.0-2-gb96a1c4+3,19.0.0-2-gd955cfd+15,19.0.0-3-g2d13df8,19.0.0-3-g6f3c7dc,19.0.0-4-g725f80e+11,19.0.0-4-ga671dab3b+1,19.0.0-4-gad373c5+3,19.0.0-5-ga2acb9c+2,19.0.0-5-gfe96e6c+2,w.2020.01
LSSTDataManagementBasePackage
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 isAttributeSafeToTransfer(name, value)
Definition: wrappers.py:45
def continueClass(cls)
Definition: wrappers.py:59

◆ 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) or
54  name in INTRINSIC_SPECIAL_ATTRIBUTES):
55  return False
56  return True
57 
58 
def isAttributeSafeToTransfer(name, value)
Definition: wrappers.py:45

Variable Documentation

◆ INTRINSIC_SPECIAL_ATTRIBUTES

lsst.utils.wrappers.INTRINSIC_SPECIAL_ATTRIBUTES

Definition at line 32 of file wrappers.py.