From PBP page 58:
If you decide not [to] use the Readonly module in production code (for performance or political reasons), then using constant is still better than using literal values.

From that quote I get the impression that TheDamian is aware of the performance issues but takes for granted that others are not as familiar. Regardless however, the performance issue is mentioned in PBP (albeit briefly).

Update: Fixed typos

In reply to Re^3: What is the difference between the constant construct in Perl and the Readonly construct in Perl? by Argel
in thread What is the difference between the constant construct in Perl and the Readonly construct in Perl? by jira0004

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