John, These codes are written by famous mod_perl expert Stas Berkman,do you know it? You can find them at: http://www.perl.com/pub/a/2002/04/23/mod_perl.html?page=1
maybe you don't know them,but it don't mean that it is impossible.Hm... -----Original Message----- >From: John Doe <[EMAIL PROTECTED]> >Sent: Jan 16, 2006 9:48 AM >To: beginners@perl.org >Subject: Re: about the var's scope > >[reordered to bottom style posting] >> -----Original Message----- >> >> >From: Shawn Corey <[EMAIL PROTECTED]> >> >Sent: Jan 15, 2006 10:58 PM >> >To: beginners@perl.org >> >Subject: Re: about the var's scope >> > >> >Jeff Pang wrote: >> >> Hello,lists, >> >> >> >> Seeing these code below please.I can't know why the var defined in the >> >> main script can been accessed in the modules that used by the main >> >> script?thanks. >> > >> > From `perldoc vars`: >> > >> >While the vars pragma cannot duplicate the effect of package lexicals >> >(total transparency outside of the package), it can act as an acceptable >> >substitute by pre-declaring global symbols, ensuring their availability >> >to the later-loaded routines. >> > >> >This means any variable declared by vars can be accessed outside of the >> >file it is declared in. >> > >> >The second part of the understanding comes from Exporter. When it >> >exports a thingy, it uses a typeglob to make the thingy in the package >> >the same as in the 'use'ing module. In other words, for your My::HTML >> >module, it does this: >> > >> > $main::q = \*My::HTML::q; >> > >> > >> >For more details, see: >> > >> > perldoc vars >> > perldoc -f our >> > perldoc perlfunc (and search for 'our') >> > >> > perldoc Exporter >> > perldoc perlop (and search for 'typeglob') >> > perldoc perlsub (and search for 'typeglob') >> > >> >Just my 0.00000002 million dollars worth, >> > --- Shawn >[...] > >Jeff Pang am Montag, 16. Januar 2006 01.59: >> Thanks for Shawn.The main script can see the global var $q coming from >> module,since the main script import this symbol via 'use My::HTML >> qw($q)'.But the modules have no any importing behavior,why they can see the >> global var $q coming from main script?I'm really confused for that. > >Ok, it would be interesting to look deeper into the mess of different >variables all named with the same name $q, exported across the modules, >overwritten by several imports... > >What do you want to achieve with your code? It looks really strange (hm, at >least to me). > >joe > >-- >To unsubscribe, e-mail: [EMAIL PROTECTED] >For additional commands, e-mail: [EMAIL PROTECTED] ><http://learn.perl.org/> <http://learn.perl.org/first-response> > > -- http://home.earthlink.net/~pangj/ -- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] <http://learn.perl.org/> <http://learn.perl.org/first-response>
