It's now Nth time that I run into this problem; however, this time I have enough resolve to learn more on how to avoid it in the future.

When I use both 'strict' and 'diagnostics' here's what I get whenever i attempt to execute my script:

-----------------------
Name "CONFIG::foo" used only once: possible typo at foo_script.pl line 181 (#1)

(W) Typographical errors often show up as unique variable names. If you had a good reason for having a unique name, then just mention it again somehow to suppress the message. The use vars pragma is provided for just this purpose.
-----------------------


Consider $CONFIG::foo being one of a few variables inside my CONFIG package used inside the main script. A few of the variables defined inside the CONFIG package are not used more than a single time. Consequently this causes a problem with perl as mentioned above.

According to the 'diagnostics' comment, one way to resolve this would be to "mention it again somehow..." (where 'it' is the variable). So, just how do I do it best? The whole idea of 'mentioning' a variable an extra time in order to avoid warnings is a little hard for me to grasp. I realize that one way (out of hundreds..) of doing this would be: 
my $temp = $CONFIG::foo;

[download]
The question I have though is that it doesn't look at all normal to do it this way. I also tried playing with this: 
use vars qw($CONFIG::foo);

[download]
However, to no surprise, it wouldn't let me 'redeclare' variables belonging to an 'alien' package (and therefore already 'defined'). Finally, could such a warning really attribute to poor code/logic design? Is it really so wrong and sinful to have a variable (mainly in a configuration package) to be used only once in the main code?
Please help with whatever may come to your mind ;-).

"There is no system but GNU, and Linux is one of its kernels." -- Confession of Faith

In reply to Unique variable names & 'strict vars' by vladb

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