use diagnostics (Re: Readonly variable)

[tye]

But I thought that at least part of the point of diagnostics.pm was for people with scars to collect the likely list of reasons for each error.

        - tye (but my friends call me "Tye")

[tilly]

True, but consider my point an addendum to point 8 of japhy's advice. Perl can tell you that it is seeing something invalid and describe in great detail why it is invalid. But it takes some experience to make from that an educated guess for why perl is getting invalid data. Since that is probably the question that has to be answered in the end anyways, that is very valuable. But unfortunately it isn't as easily bottled up into a module...