ikan Uploader :
Directory : /lib64/python3.6/__pycache__/
Upload File : |
| Current File : //lib64/python3.6/__pycache__/contextlib.cpython-36.pyc |
3
\j3 � @ s� d Z ddlZddlZddlZddlmZ ddlmZ ddddd d
d d gZG d
d� dej �Z
G dd� de �Z G dd� de e
�Z
dd� ZG dd� de
�ZG dd� de
�ZG dd
� d
e�ZG dd � d e�ZG dd � d e
�ZG dd � d e
�ZdS )z4Utilities for with-statement contexts. See PEP 343.� N)�deque)�wraps�contextmanager�closing�AbstractContextManager�ContextDecorator� ExitStack�redirect_stdout�redirect_stderr�suppressc @ s2 e Zd ZdZdd� Zejdd� �Zedd� �Z dS ) r z,An abstract base class for context managers.c C s | S )z0Return `self` upon entering the runtime context.� )�selfr r �"/usr/lib64/python3.6/contextlib.py� __enter__ s z AbstractContextManager.__enter__c C s dS )z9Raise any exception triggered within the runtime context.Nr )r
�exc_type� exc_value� tracebackr r r �__exit__ s z AbstractContextManager.__exit__c C s | t krtj|dd�S tS )Nr r )r �_collections_abc�_check_methods�NotImplemented)�cls�Cr r r �__subclasshook__ s z'AbstractContextManager.__subclasshook__N)
�__name__�
__module__� __qualname__�__doc__r �abc�abstractmethodr � classmethodr r r r r r
s c @ s e Zd ZdZdd� Zdd� ZdS )r zJA base class or mixin that enables context managers to work as decorators.c C s | S )a6 Return a recreated instance of self.
Allows an otherwise one-shot context manager like
_GeneratorContextManager to support use as
a decorator via implicit recreation.
This is a private interface just for _GeneratorContextManager.
See issue #11647 for details.
r )r
r r r � _recreate_cm$ s
z ContextDecorator._recreate_cmc s t � �� �fdd��}|S )Nc
s �j � � � | |�S Q R X d S )N)r! )�args�kwds)�funcr
r r �inner1 s
z(ContextDecorator.__call__.<locals>.inner)r )r
r$ r% r )r$ r
r �__call__0 s zContextDecorator.__call__N)r r r r r! r& r r r r r ! s c @ s0 e Zd ZdZdd� Zdd� Zdd� Zdd � Zd
S ) �_GeneratorContextManagerz%Helper for @contextmanager decorator.c C sJ |||�| _ ||| | _| _| _t|dd �}|d kr@t| �j}|| _d S )Nr )�genr$ r" r# �getattr�typer )r
r$ r" r# �docr r r �__init__; s
z!_GeneratorContextManager.__init__c C s | j | j| j| j�S )N)� __class__r$ r" r# )r
r r r r! I s z%_GeneratorContextManager._recreate_cmc C s. y
t | j�S tk
r( td�d �Y nX d S )Nzgenerator didn't yield)�nextr( �
StopIteration� RuntimeError)r
r r r r O s
z"_GeneratorContextManager.__enter__c C s� |d kr6yt | j� W n tk
r* dS X td��n�|d krD|� }y| jj|||� W n� tk
r| } z||k S d }~X nf tk
r� } z*||kr�dS |tkr�|j|kr�dS � W Y d d }~X n" tj� d |kr�dS � Y nX td��d S )NFzgenerator didn't stop� z#generator didn't stop after throw())r. r( r/ r0 �throw� __cause__�sys�exc_info)r
r* �valuer �excr r r r U s.
z!_GeneratorContextManager.__exit__N)r r r r r, r! r r r r r r r' 8 s
r' c s t � �� fdd��}|S )a� @contextmanager decorator.
Typical usage:
@contextmanager
def some_generator(<arguments>):
<setup>
try:
yield <value>
finally:
<cleanup>
This makes this:
with some_generator(<arguments>) as <variable>:
<body>
equivalent to this:
<setup>
try:
<variable> = <value>
<body>
finally:
<cleanup>
c s t � | |�S )N)r' )r" r# )r$ r r �helper� s z contextmanager.<locals>.helper)r )r$ r8 r )r$ r r � s c @ s( e Zd ZdZdd� Zdd� Zdd� ZdS ) r a2 Context to automatically close something at the end of a block.
Code like this:
with closing(<module>.open(<arguments>)) as f:
<block>
is equivalent to this:
f = <module>.open(<arguments>)
try:
<block>
finally:
f.close()
c C s
|| _ d S )N)�thing)r
r9 r r r r, � s zclosing.__init__c C s | j S )N)r9 )r
r r r r � s zclosing.__enter__c G s | j j� d S )N)r9 �close)r
r5 r r r r � s zclosing.__exit__N)r r r r r, r r r r r r r � s c @ s( e Zd ZdZdd� Zdd� Zdd� ZdS )�_RedirectStreamNc C s || _ g | _d S )N)� _new_target� _old_targets)r
�
new_targetr r r r, � s z_RedirectStream.__init__c C s* | j jtt| j�� tt| j| j� | jS )N)r= �appendr) r4 �_stream�setattrr< )r
r r r r � s z_RedirectStream.__enter__c C s t t| j| jj� � d S )N)rA r4 r@ r= �pop)r
�exctype�excinst�exctbr r r r � s z_RedirectStream.__exit__)r r r r@ r, r r r r r r r; � s r; c @ s e Zd ZdZdZdS )r aA Context manager for temporarily redirecting stdout to another file.
# How to send help() to stderr
with redirect_stdout(sys.stderr):
help(dir)
# How to write help() to a file
with open('help.txt', 'w') as f:
with redirect_stdout(f):
help(pow)
�stdoutN)r r r r r@ r r r r r � s c @ s e Zd ZdZdZdS )r
zCContext manager for temporarily redirecting stderr to another file.�stderrN)r r r r r@ r r r r r
� s c @ s( e Zd ZdZdd� Zdd� Zdd� ZdS ) r a? Context manager to suppress specified exceptions
After the exception is suppressed, execution proceeds with the next
statement following the with statement.
with suppress(FileNotFoundError):
os.remove(somefile)
# Execution still resumes here if the file was already removed
c G s
|| _ d S )N)� _exceptions)r
�
exceptionsr r r r, � s zsuppress.__init__c C s d S )Nr )r
r r r r � s zsuppress.__enter__c C s |d k ot || j�S )N)�
issubclassrH )r
rC rD rE r r r r � s
zsuppress.__exit__N)r r r r r, r r r r r r r � s c @ sP e Zd ZdZdd� Zdd� Zdd� Zdd � Zd
d � Zd d
� Z dd� Z
dd� Z dS )r a� Context manager for dynamic management of a stack of exit callbacks
For example:
with ExitStack() as stack:
files = [stack.enter_context(open(fname)) for fname in filenames]
# All opened files will automatically be closed at the end of
# the with statement, even if attempts to open files later
# in the list raise an exception
c C s t � | _d S )N)r �_exit_callbacks)r
r r r r, s zExitStack.__init__c C s t | �� }| j|_t� | _|S )z?Preserve the context stack by transferring it to a new instance)r* rK r )r
� new_stackr r r �pop_all s
zExitStack.pop_allc s" � �fdd�}� |_ | j|� dS )z:Helper to correctly register callbacks to __exit__ methodsc s �� f| �� S )Nr )� exc_details)�cm�cm_exitr r �
_exit_wrapper s z.ExitStack._push_cm_exit.<locals>._exit_wrapperN)�__self__�push)r
rO rP rQ r )rO rP r �
_push_cm_exit s zExitStack._push_cm_exitc C sD t |�}y
|j}W n tk
r2 | jj|� Y nX | j||� |S )a Registers a callback with the standard __exit__ method signature
Can suppress exceptions the same way __exit__ methods can.
Also accepts any object with an __exit__ method (registering a call
to the method instead of the object itself)
)r* r �AttributeErrorrK r? rT )r
�exit�_cb_type� exit_methodr r r rS s
zExitStack.pushc s$ � ��fdd�}�|_ | j|� �S )z\Registers an arbitrary callback and arguments.
Cannot suppress exceptions.
c s �� �� d S )Nr )r r7 �tb)r" �callbackr# r r rQ 9 s z)ExitStack.callback.<locals>._exit_wrapper)� __wrapped__rS )r
rZ r" r# rQ r )r" rZ r# r rZ 4 s
zExitStack.callbackc C s( t |�}|j}|j|�}| j||� |S )z�Enters the supplied context manager
If successful, also pushes its __exit__ method as a callback and
returns the result of the __enter__ method.
)r* r r rT )r
rO �_cm_type�_exit�resultr r r �
enter_contextA s
zExitStack.enter_contextc C s | j ddd� dS )z$Immediately unwind the context stackN)r )r
r r r r: N s zExitStack.closec s� |d d k }t j� d � � fdd�}d}d}x\| jr�| jj� }y||� rTd}d}d}W q. t j� }||d |d � d}|}Y q.X q.W |r�y|d j}|d �W n tk
r� ||d _� Y nX |o�|S )Nr r1 c s8 x,| j }||krd S |d ks$|� kr&P |} qW || _ d S )N)� __context__)�new_exc�old_exc� exc_context)� frame_excr r �_fix_exception_contextX s z2ExitStack.__exit__.<locals>._fix_exception_contextFT)NNN)r4 r5 rK rB r` �
BaseException) r
rN � received_excre �suppressed_exc�
pending_raise�cb�new_exc_details� fixed_ctxr )rd r r R s2
zExitStack.__exit__N) r r r r r, rM rT rS rZ r_ r: r r r r r r s
)r r r4 r � collectionsr � functoolsr �__all__�ABCr �objectr r' r r r; r r
r r r r r r �<module> s$ I"
........