Is automatic reload of a module available in Python?

[Arnaud Delobelle]

"R (Chandra) Chandrasekhar" <chyavana at gmail.com> writes:

> Dear Folks,
>
> I am currently developing a python program, let us call it
> "generic.py", and I am testing out the functions therein by testing
> them out interactively in the python interpreter by invoking python
> and doing
>
> import generic
>
> Once I hit an error, I need to revise my file and reload the module using
>
> reload(generic)
>
> The difference in syntax between invoking import and reload is really
> costing me time and patience.
>
> Therefore, I would like to ask:
>
> 1. Is there a method of auto-reloading a module while developing it
> and testing it with the interactive python interpreter?
>
> 2. Is there a better way of developing a program?
>
> Thank you.
>
> Chandra

Here is a very simple way to improve what you do, which won't require
you to change the way you work or to learn a new paradigm:

Instead of testing your functions interactively, put your testing code
in a file, e.g. 'program_tests.py'.  Your can then type

    python program_tests.py

at the shell interactive prompt.  To perform the tests again, just
re-execute that file.  If your tests are divided into
different units, you can put these in functions:

    def test_frobz():
        #testing code for frobzation of klops

    def test_frizz():
        #testing code for frizzment of frobzied klops

    # etc..

So if you want to keep doing interactive tests, you can import
program_tests and call whichever testing functions you want.  You may
even have arguments to those functions to test them with different
parameters.

I know some people will point at more 'pro' ways of testing but this has
the merit of being very straightforward.  Then when you move on to more
sophisticated techniques, I think you will understand better the
motivations behind them.

-- 
Arnaud