Commit 48367816 authored by Georg Brandl's avatar Georg Brandl

Manually merged r67583: move __import__ doc to the bottom.

parent f7d4874c
...@@ -8,59 +8,6 @@ The Python interpreter has a number of functions and types built into it that ...@@ -8,59 +8,6 @@ The Python interpreter has a number of functions and types built into it that
are always available. They are listed here in alphabetical order. are always available. They are listed here in alphabetical order.
.. function:: __import__(name[, globals[, locals[, fromlist[, level]]]])
.. index::
statement: import
module: imp
.. note::
This is an advanced function that is not needed in everyday Python
programming.
The function is invoked by the :keyword:`import` statement. It mainly exists
so that you can replace it with another function that has a compatible
interface, in order to change the semantics of the :keyword:`import`
statement. See the built-in module :mod:`imp`, which defines some useful
operations out of which you can build your own :func:`__import__` function.
For example, the statement ``import spam`` results in the following call:
``__import__('spam', globals(), locals(), [], -1)``; the statement
``from spam.ham import eggs`` results in ``__import__('spam.ham', globals(),
locals(), ['eggs'], -1)``. Note that even though ``locals()`` and ``['eggs']``
are passed in as arguments, the :func:`__import__` function does not set the
local variable named ``eggs``; this is done by subsequent code that is generated
for the import statement. (In fact, the standard implementation does not use
its *locals* argument at all, and uses its *globals* only to determine the
package context of the :keyword:`import` statement.)
When the *name* variable is of the form ``package.module``, normally, the
top-level package (the name up till the first dot) is returned, *not* the
module named by *name*. However, when a non-empty *fromlist* argument is
given, the module named by *name* is returned. This is done for
compatibility with the :term:`bytecode` generated for the different kinds of import
statement; when using ``import spam.ham.eggs``, the top-level package
:mod:`spam` must be placed in the importing namespace, but when using ``from
spam.ham import eggs``, the ``spam.ham`` subpackage must be used to find the
``eggs`` variable. As a workaround for this behavior, use :func:`getattr` to
extract the desired components. For example, you could define the following
helper::
def my_import(name):
mod = __import__(name)
components = name.split('.')
for comp in components[1:]:
mod = getattr(mod, comp)
return mod
*level* specifies whether to use absolute or relative imports. The default is
``-1`` which indicates both absolute and relative imports will be attempted.
``0`` means only perform absolute imports. Positive values for *level* indicate
the number of parent directories to search relative to the directory of the
module calling :func:`__import__`.
.. function:: abs(x) .. function:: abs(x)
Return the absolute value of a number. The argument may be an Return the absolute value of a number. The argument may be an
...@@ -1220,6 +1167,59 @@ are always available. They are listed here in alphabetical order. ...@@ -1220,6 +1167,59 @@ are always available. They are listed here in alphabetical order.
True True
.. function:: __import__(name[, globals[, locals[, fromlist[, level]]]])
.. index::
statement: import
module: imp
.. note::
This is an advanced function that is not needed in everyday Python
programming.
The function is invoked by the :keyword:`import` statement. It mainly exists
so that you can replace it with another function that has a compatible
interface, in order to change the semantics of the :keyword:`import`
statement. See the built-in module :mod:`imp`, which defines some useful
operations out of which you can build your own :func:`__import__` function.
For example, the statement ``import spam`` results in the following call:
``__import__('spam', globals(), locals(), [], -1)``; the statement
``from spam.ham import eggs`` results in ``__import__('spam.ham', globals(),
locals(), ['eggs'], -1)``. Note that even though ``locals()`` and ``['eggs']``
are passed in as arguments, the :func:`__import__` function does not set the
local variable named ``eggs``; this is done by subsequent code that is generated
for the import statement. (In fact, the standard implementation does not use
its *locals* argument at all, and uses its *globals* only to determine the
package context of the :keyword:`import` statement.)
When the *name* variable is of the form ``package.module``, normally, the
top-level package (the name up till the first dot) is returned, *not* the
module named by *name*. However, when a non-empty *fromlist* argument is
given, the module named by *name* is returned. This is done for
compatibility with the :term:`bytecode` generated for the different kinds of import
statement; when using ``import spam.ham.eggs``, the top-level package
:mod:`spam` must be placed in the importing namespace, but when using ``from
spam.ham import eggs``, the ``spam.ham`` subpackage must be used to find the
``eggs`` variable. As a workaround for this behavior, use :func:`getattr` to
extract the desired components. For example, you could define the following
helper::
def my_import(name):
mod = __import__(name)
components = name.split('.')
for comp in components[1:]:
mod = getattr(mod, comp)
return mod
*level* specifies whether to use absolute or relative imports. The default is
``-1`` which indicates both absolute and relative imports will be attempted.
``0`` means only perform absolute imports. Positive values for *level* indicate
the number of parent directories to search relative to the directory of the
module calling :func:`__import__`.
.. rubric:: Footnotes .. rubric:: Footnotes
.. [#] Specifying a buffer size currently has no effect on systems that don't have .. [#] Specifying a buffer size currently has no effect on systems that don't have
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