[Python-Dev] requirements for moving __import__ over to importlib?

[Terry Reedy]

On 2/8/2012 3:16 PM, Brett Cannon wrote:
> On Wed, Feb 8, 2012 at 14:57, Terry Reedy <tjreedy at udel.edu
>     Would the following work? Treat a function as a 'loop' in that it
>     may be executed repeatedly. Treat 'import x' in a function as what
>     it is, an __import__ call plus a local assignment. Apply a version
>     of the usual optimization: put a sys.modules-based lazy import
>     outside of the function (at the top of the module?) and leave the
>     local assignment "x = sys.modules['x']" in the function. Change
>     sys.modules.__delattr__ to replace a module with a dummy, so the
>     function will still work after a deletion, as it does now.
>
> Probably, but I would hate to force people to code in a specific way for
> it to work.

The intent of what I proposed it to be transparent for imports within 
functions. It would be a minor optimization if anything, but it would 
mean that there is a lazy mechanism in place.

For top-level imports, unless *all* are made lazy, then there *must* be 
some indication in the code of whether to make it lazy or not.

-- 
Terry Jan Reedy