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Re: Help needed understanding global variables in Perl

by rinceWind (Monsignor)
on Mar 05, 2002 at 09:19 UTC ( #149309=note: print w/replies, xml ) Need Help??


in reply to Help needed understanding global variables in Perl

Dear Anonymous Monk,

you have a number of questions rolled into your query. My first piece of advice is to read perlsub in the core documentation, if you have not already done so.

Why do you need global variables? You rarely need them in C. If you are wanting to preserve state information between subroutine calls, you should look at using a class, see perltoot object tutorial, or a closure, see Funkyness with closures....

Also, if the declaration of the sub is inside a block, it has access to 'my' variables declared in the block before the sub, which will keep their value between calls.

Hope this helps and I haven't confused you too much

--rW

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Re: Re: Help needed understanding global variables in Perl
by rbrito (Acolyte) on Mar 06, 2002 at 02:48 UTC

    Oh, sure, I understand that global variables are bad in practice (read: "the real world"). But my question was more theoretic, in the sense that I'm just trying to have a solid background on the language and understand its semantics from the viewpoint of a user.

    Unfortunately, I still have not understood completely the use of (user-defined) global variables with Perl.

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