[Python-Dev] Re: Allow all assignment expressions after 'import something as' (original) (raw)

Thomas Wouters thomas@xs4all.net
Thu, 24 Aug 2000 12🔞58 +0200

On Thu, Aug 24, 2000 at 04:14:12AM -0500, Ka-Ping Yee wrote:

The current explanation of "import as " is something like

Find and import the module named and assign it to in the normal way you do assignment, except has to be a pure name.

Thomas' suggestion lifts the restriction and makes the explanation simpler than it would have been:

Find and import the module named and assign it to in the normal way you do assignment.

"The normal way you do assignment" is shorthand for "decide whether to assign to the local or global namespace depending on whether has been assigned to in the current scope, unless has been declared global with a 'global' statement" -- and that applies in any case. Luckily, it's a concept that has been explained before and which Python programmers already need to understand anyway.

This is not true. The current situation already does the local/global namespace trick, except that 'import ..' is a local assignment, so the resulting name is always local (unless there is a "global" statement.)

My patch wouldn't change that one bit. It would only expand the allowable expressions in the 'as' clause: is it a normal name-binding assignment (like now), or a subscription-assignment, or a slice-assignment, or an attribute-assignment. In other words, all types of assignment.

The net effect is essentially a direct translation to

= import("")

Exactly :)

Careful:

import foo.bar "import the package named foo and its submodule bar, then put foo into the current namespace"

Wrong. What it does is: import the package named foo and its submodule bar, and make it so you can access foo.bar via the name 'foo.bar'. That this has to put 'foo' in the local namespace is a side issue :-) And when seen like that,

import foo.bar as spam "import the package named foo and its submodule bar, then put bar into the current namespace, as spam"

Becomes obvious as well.

-- Thomas Wouters <thomas@xs4all.net>

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