Your question is not very clear to me, but, contrary to others who suggested to use references, I understand that you do NOT want the content of the hash to change when you change some variables in the environment. If you do this: 
$test = 'test';
%hash = ( t => $test);
$test = 'changed';

[download]
the content of the hash does not change, it is still 'test', because the assignment: 
%hash = ( t => $test);

[download]
is storing into the hash the content of the $test variable at the time this assignment is done. Modifying the $test variable afterwards will not modify the content of the hash.

But if you do: 

$change = 'changed';
$hash{t} = $change;

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then, of course the value in the hash will be modified because that's precisely a common way to modify the content of a hash for a given key.

Je suis Charlie.

In reply to Re: Changing a variable which is a value of a hash by Laurent_R
in thread Changing a variable which is a value of a hash by benedicth

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