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Hi,

A key feature (in my view) of Readonly that others haven't mentioned yet is that a Readonly hashref will prevent you from modifying the referenced hash. The constant pragma, in contrast, only prevents you from changing the top-level reference value. The constant will always point to the same hash, but that hash can be modified. Maybe this might change in future, I don't know, but in the meantime I've been bitten by this not-entirely-constant nature of the constant pragma (inadvertently using a "constant" hash as a global variable...). It's fine for scalar and array values, but a bit dodgy for hashes, IMHO.

cheers,
Tim


In reply to Re: What is the difference between the constant construct in Perl and the Readonly construct in Perl? by tfrayner
in thread What is the difference between the constant construct in Perl and the Readonly construct in Perl? by jira0004

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