FYI. Perl 5.18 with Readonly 2.0 behaves the same as you have - just uninitialised value error.

Using Perl 5.14 with Readonly 1.3: 

Type of arg 1 to Readonly::Readonly must be one of [$@%]
 (not scalar assignment) near "'bar';"
Type of arg 1 to Readonly::Readonly must be one of [$@%]
 (not list assignment) near ");"

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I compared the source of Readonly 1.3 with 2.0 and couldn't see any obvious difference. Will need to try v1.3 and v2.0 with the same version of Perl.

In reply to Re: Readonly oddity by tangent
in thread Readonly oddity by Anonymous Monk

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