diff options
Diffstat (limited to 'Doc/library/inspect.rst')
| -rw-r--r-- | Doc/library/inspect.rst | 68 |
1 files changed, 60 insertions, 8 deletions
diff --git a/Doc/library/inspect.rst b/Doc/library/inspect.rst index d4cf905..ccb2bd7 100644 --- a/Doc/library/inspect.rst +++ b/Doc/library/inspect.rst @@ -69,7 +69,12 @@ attributes: | | | :term:`bytecode` | +-----------+-----------------+---------------------------+ | | __defaults__ | tuple of any default | -| | | values for arguments | +| | | values for positional or | +| | | keyword parameters | ++-----------+-----------------+---------------------------+ +| | __kwdefaults__ | mapping of any default | +| | | values for keyword-only | +| | | parameters | +-----------+-----------------+---------------------------+ | | __globals__ | global namespace in which | | | | this function was defined | @@ -173,8 +178,9 @@ attributes: .. note:: - :func:`getmembers` does not return metaclass attributes when the argument - is a class (this behavior is inherited from the :func:`dir` function). + :func:`getmembers` will only return class attributes defined in the + metaclass when the argument is a class and those attributes have been + listed in the metaclass' custom :meth:`__dir__`. .. function:: getmoduleinfo(path) @@ -428,11 +434,14 @@ function. Accepts a wide range of python callables, from plain functions and classes to :func:`functools.partial` objects. + Raises :exc:`ValueError` if no signature can be provided, and + :exc:`TypeError` if that type of object is not supported. + .. note:: Some callables may not be introspectable in certain implementations of - Python. For example, in CPython, built-in functions defined in C provide - no metadata about their arguments. + Python. For example, in CPython, some built-in functions defined in + C provide no metadata about their arguments. .. class:: Signature(parameters=None, \*, return_annotation=Signature.empty) @@ -510,9 +519,8 @@ function. .. attribute:: Parameter.name - The name of the parameter as a string. Must be a valid python identifier - name (with the exception of ``POSITIONAL_ONLY`` parameters, which can have - it set to ``None``). + The name of the parameter as a string. The name must be a valid + Python identifier. .. attribute:: Parameter.default @@ -596,6 +604,10 @@ function. >>> str(param.replace(default=Parameter.empty, annotation='spam')) "foo:'spam'" + .. versionchanged:: 3.4 + In Python 3.3 Parameter objects were allowed to have ``name`` set + to ``None`` if their ``kind`` was set to ``POSITIONAL_ONLY``. + This is no longer permitted. .. class:: BoundArguments @@ -806,6 +818,23 @@ Classes and functions .. versionadded:: 3.3 +.. function:: unwrap(func, *, stop=None) + + Get the object wrapped by *func*. It follows the chain of :attr:`__wrapped__` + attributes returning the last object in the chain. + + *stop* is an optional callback accepting an object in the wrapper chain + as its sole argument that allows the unwrapping to be terminated early if + the callback returns a true value. If the callback never returns a true + value, the last object in the chain is returned as usual. For example, + :func:`signature` uses this to stop unwrapping if any object in the + chain has a ``__signature__`` attribute defined. + + :exc:`ValueError` is raised if a cycle is encountered. + + .. versionadded:: 3.4 + + .. _inspect-stack: The interpreter stack @@ -838,6 +867,10 @@ index of the current line within that list. finally: del frame + If you want to keep the frame around (for example to print a traceback + later), you can also break reference cycles by using the + :meth:`frame.clear` method. + The optional *context* argument supported by most of these functions specifies the number of lines of context to return, which are centered around the current line. @@ -994,3 +1027,22 @@ updated as expected: return an empty dictionary. .. versionadded:: 3.3 + + +.. _inspect-module-cli: + +Command Line Interface +---------------------- + +The :mod:`inspect` module also provides a basic introspection capability +from the command line. + +.. program:: inspect + +By default, accepts the name of a module and prints the source of that +module. A class or function within the module can be printed instead by +appended a colon and the qualified name of the target object. + +.. cmdoption:: --details + + Print information about the specified object rather than the source code |