A Better reason that I find for using Readonly is that is makes your code easier to understand. If you do not have Readonly with XS compiled then you take a performance hit but you generally only see that using a Readonly hash.

Another Advantage Readonly has over use constant is that you can declare a hash, you cannot do that with use constant.

In reply to Re^3: Using Constants in Perl by Anonymous Monk
in thread Using Constants in Perl by qazwart

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