Re^4: Does there exist a CPAN module for lazily initialized variables?

[jryan]

Yeah, my little class in the root node would do the same thing, since it just checks for definedness. I just want a pretty tied interface to it. I guess I'll just write my own class, and maybe make it general enough for CPAN...

[diotalevi]

No, the difference here is that you make this call $dbh->connect_cached() so that instead of just storing your object - you revivify it automatically as needed. I think of this as important for something that will be long running - I'd just go with a plain stored value otherwise.

sub main::dbh
{
    # for daemons and long running code - reconnect as needed
    DBI->connect_cached( ... )
}

sub main::dbh
{
    # initialize the connection or re-use.
    $::DBH ||= DBI->connect( ... )
}

[jryan]

Wouldn't that be something to change in the callback sub that you'd pass to the tie call?

[diotalevi]

Sure you could, but I wouldn't bother tying it at this point. You have to have one globally accessible symbol by which to reach this connection. Either it happens explicitly through &::dbh() or implicitly through tied $::dbh. I'd generally prefer to leave off with the tying to avoid excessive cuteness.