ok, thank you,
but I have to declare
another:

our $test='hello';
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otherwise I have that error:

Global symbol "$test" requires explicit package name at myFile.pl line
+ 16.
Execution of myFile.pl aborted due to compilation errors.
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Thank you for your advise about exporting variable. I will not export them:
$test was just a test.
I will export just some constants, useful to define my environement in whole package