Here is what I did come up with through the education/help received in this thread:

# set debugging switch to OFF
my $debug_switch = 0;

# go through the argument evaluation at compile time
BEGIN
{
    # check each argument
    foreach $_ (@ARGV)
    {
        # is the debug switch submitted?
        if (/^-d$/i)
        {
            # yup. set debugging switch to ON
            $debug_switch = 1;
        }
    }
}
# set DEBUGGING to the debug_switch value
use constant DEBUGGING => $debug_switch;

[download]

It works, doesn't throw any warnings, and I use a constant like it is normally done: Define once, use x times.

In reply to Re: (tye)Re: change 'use constant' value through commandline arguments? by neuroball
in thread change 'use constant' value through commandline arguments? by neuroball

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