I am writing on a template module that allows embedding perl code which is then evaled within the modues namespace. As a side effect the templates can override a subroutines like in 

    *HSP::echo = sub {
        do something other than it normally would
    };

[download]

Running as CGI there is no problem with it. But embedding perl in HTML makes more sense when running under mod_perl. With mod_perl the modified subroutine stays modified. If someone does

    *HSP::echo = sub{ die };

then the system doesn't work anymore because it allways dies when it wants to print something out.

I know that I can make a subroutine private by saying my $sub = sub{ something private }; but since the templates are eval()ed in the same namespace it would also be possible to undef $sub. Am I lost now? Does someone know of a way how to protect a subroutine from being overridden? Something like this 

    sub echo : protected {
        do something
    }

[download]
would be ideal maybe together with die "You are not allowed to override this subroutine".

In reply to Overriding Subroutines in Package by Tetramin

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