A beginner's problem...

[Amir Dekel]

Hello everyone,

First, I have to say that Python is one of the coolest programing
languages I have seen.
And now for the problem (must be a silly one):
When I import a module I have wrote, and then I find bugs, it seems that
I can't import it again after a fix it. It always shows the same
problem. I try del module but it doesn't work.
(I use Python 2.4 with the ActivePython pack (PythonWin IDE)

Solution anyone?

Amir

 

[Robert P. J. Day]

Hello everyone,

First, I have to say that Python is one of the coolest programing languages I
have seen.
And now for the problem (must be a silly one):
When I import a module I have wrote, and then I find bugs, it seems that I
can't import it again after a fix it. It always shows the same problem. I try
del module but it doesn't work.
(I use Python 2.4 with the ActivePython pack (PythonWin IDE)

Solution anyone?

reload?

rday

 

[Marc 'BlackJack' Rintsch]

When I import a module I have wrote, and then I find bugs, it seems that
I can't import it again after a fix it. It always shows the same
problem. I try del module but it doesn't work.
(I use Python 2.4 with the ActivePython pack (PythonWin IDE)

Solution anyone?

Yes -> help(reload)

Ciao,
Marc 'BlackJack' Rintsch

 

[DogWalker]

Yes -> help(reload)

Ciao,
Marc 'BlackJack' Rintsch

First, save the file using the check option (Ctl+Shift+C, iirc);
Second, Fix any errors (attend to Status Bar);
Third, press Reload button in Toolbar (or type command from File Menu).
Four, assure that Status Bar indicates reload was successful.
If still doesn't load correctly, quit PythonWin and start it again.

 

[Christian Ergh]

First, save the file using the check option (Ctl+Shift+C, iirc);
Second, Fix any errors (attend to Status Bar);
Third, press Reload button in Toolbar (or type command from File Menu).
Four, assure that Status Bar indicates reload was successful.
If still doesn't load correctly, quit PythonWin and start it again.

Fifth, use the module unittest and write a test for your module. Just
run the test to check your module and fix all errors, then import it
into the larger sceme and see if everything works there. Most problems
will appear in a good test, so you will not have the reimport issiue at all.
Chris

 

[James Martin]

Try deleting the Compiled Python File that was created during import --
extension pyc. Then import again.

It seems to me (I'm a novice too) that, when you import a module, Python
automatically compiles it. Then when you import it later, the compiled
version is imported if it exists.

 

[Mike Meyer]

[Format recovered from top posting.]

Try deleting the Compiled Python File that was created during import --
extension pyc. Then import again.

It seems to me (I'm a novice too) that, when you import a module, Python
automatically compiles it. Then when you import it later, the compiled
version is imported if it exists.

It compares the dates on the .py file with the .pyc file, and
recompiles the .py file if it's newer.

Doing a second import will find the module in sys.modules and not
bother looking in the file system. The solution is to reload(module)
instead of import module.

<mike

 

[Amir Dekel]

Doing a second import will find the module in sys.modules and not
bother looking in the file system. The solution is to reload(module)
instead of import module.

<mike

What if I import using "from module import class"? It seems to me that I
can't use reload then, or I just couldn't find the right syntax...

 

[Mike Meyer]

What if I import using "from module import class"? It seems to me that
I can't use reload then, or I just couldn't find the right syntax...

I'm pretty sure you'll have to import the module and reload it. "from
module import class" still puts the module in sys.modules, so trying
to import something from it again will find it in there.

<mike

 

[Nick Coghlan]

What if I import using "from module import class"? It seems to me that I
can't use reload then, or I just couldn't find the right syntax...

Correct. Using a non-from import is actually easier when experimenting, since
reload is easier to use.

If you have used a from-style import, you have to do this to force a reload of
the relevant class:

Py> from module import x
Py> # Do stuff
Py> import module
Py> reload(module)
Py> from module import x
Py> # We now have the updated version of x

Cheers,
Nick.