* About

I needed a way to demonstrate how to properly source from another
file. Bash doesn't work quite the same as other languages, such as
python, because it will silently clobber a function.


We should take note that sourcing the same scope will help avoid
unintended clobbering.


main shows how to properly write the code while wrong shows the bad
ways. Both scripts just run a series of tests.


module1.sh and module2.sh both reside in the same directory as the
scripts. But module3.sh and module4.sh have different locations and
the fomer sources from the latter.


* Troubleshooting

Improper sourcing can lead to some very strange errors, sometimes
filling up the stdout or stderr with repeat "No such file or
directory" prompts even for just one improper sourcing. One might need
to C-c the script. But it should display the file and LOC of the
error.
