Install libreadonly-perl by entering the following commands in the terminal:
sudo apt update sudo apt install libreadonly-perl
Description:
facility for creating read-only scalars, arrays and hashes
Readonly is a facility for creating non-modifiable variables. This is useful for configuration files, headers, etc. It can also be useful as a development and debugging tool, for catching updates to variables that should not be changed.
Homepage: https://metacpan.org/release/Readonly
Version: 2.050-1
Section: universe/perl