While it would be possible to create a class to encapsulate the behaviour, or a tied variable that forbids storage of non-email addresses.. I don't think it is particularly wise to do so.

Why not just validate the user input early on, and send them back to the form entry if they do not provide an email address? I am fond of using Data::FormValidator and HTML::FillInForm for this. If you use CGI::Application then CGI::Application::Plugin::ValidateRM encapsulates this behaviour for you quite nicely.

In reply to Re: variables as classes by imp
in thread variables as classes by nmerriweather

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