Importing modules from within other modules

[Tobiah]

Hi,

If I write a module for general purpose use
that needs say, 'sys', 'os', 're' etc...
and I import those modules from within my module,
does this cause inefficiency when an existing program
that already imports these modules, imports mine,
or is there a safeguard similar to #ifdef MODULE_NAME
used in the C preprossessor?

Thanks,

Tobiah

[John Roth]

"Tobiah" <to**@rcsreg.com> wrote in message
news:82******************************@news.teranew s.com...

Hi,

If I write a module for general purpose use
that needs say, 'sys', 'os', 're' etc...
and I import those modules from within my module,
does this cause inefficiency when an existing program
that already imports these modules, imports mine,
or is there a safeguard similar to #ifdef MODULE_NAME
used in the C preprossessor?
Python will only import a module once; if you ask for it
again, you'll get the reference that Python stores in an
internal table.

It's possible to get an incompletely loaded module if you
have two modules that import each other. That's a very
messy situation called a circular import, but you actually
have to do it to get into trouble.

John Roth

Thanks,

Tobiah

[Tobiah]

> Python will only import a module once;

Thanks, this clears things up.

Tobiah