| """ |
| Module defining global singleton classes. |
| |
| This module raises a RuntimeError if an attempt to reload it is made. In that |
| way the identities of the classes defined here are fixed and will remain so |
| even if numpy itself is reloaded. In particular, a function like the following |
| will still work correctly after numpy is reloaded:: |
| |
| def foo(arg=np._NoValue): |
| if arg is np._NoValue: |
| ... |
| |
| That was not the case when the singleton classes were defined in the numpy |
| ``__init__.py`` file. See gh-7844 for a discussion of the reload problem that |
| motivated this module. |
| |
| """ |
| from __future__ import division, absolute_import, print_function |
| |
| __ALL__ = [ |
| 'ModuleDeprecationWarning', 'VisibleDeprecationWarning', '_NoValue' |
| ] |
| |
| |
| # Disallow reloading this module so as to preserve the identities of the |
| # classes defined here. |
| if '_is_loaded' in globals(): |
| raise RuntimeError('Reloading numpy._globals is not allowed') |
| _is_loaded = True |
| |
| |
| class ModuleDeprecationWarning(DeprecationWarning): |
| """Module deprecation warning. |
| |
| The nose tester turns ordinary Deprecation warnings into test failures. |
| That makes it hard to deprecate whole modules, because they get |
| imported by default. So this is a special Deprecation warning that the |
| nose tester will let pass without making tests fail. |
| |
| """ |
| |
| |
| ModuleDeprecationWarning.__module__ = 'numpy' |
| |
| |
| class VisibleDeprecationWarning(UserWarning): |
| """Visible deprecation warning. |
| |
| By default, python will not show deprecation warnings, so this class |
| can be used when a very visible warning is helpful, for example because |
| the usage is most likely a user bug. |
| |
| """ |
| |
| |
| VisibleDeprecationWarning.__module__ = 'numpy' |
| |
| |
| class _NoValueType(object): |
| """Special keyword value. |
| |
| The instance of this class may be used as the default value assigned to a |
| deprecated keyword in order to check if it has been given a user defined |
| value. |
| """ |
| __instance = None |
| def __new__(cls): |
| # ensure that only one instance exists |
| if not cls.__instance: |
| cls.__instance = super(_NoValueType, cls).__new__(cls) |
| return cls.__instance |
| |
| # needed for python 2 to preserve identity through a pickle |
| def __reduce__(self): |
| return (self.__class__, ()) |
| |
| def __repr__(self): |
| return "<no value>" |
| |
| |
| _NoValue = _NoValueType() |