Re: BEGIN { } block

because BEGING{} is an implicitly called subroutine in Perl, it can hold any initialization code, You would probably need to use BEGIN{} as a package constructor

package foo;
  BEGIN{
        $text = "Hello\n";
        }
sub subroutine {print $text} return 1;
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now after having initialized $text you can use it in code that calls foo code

require foo;
foo::subroutine();

#will print

Hello
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Other features of BEGIN{}:

it is run early when your code is compiled (even before the rest of the file is parsed).
you can use multiple BEGIN{} in the package and Perl will execute them by order of encounter.

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Re^2: BEGIN { } block by JadeNB (Chaplain) on Aug 07, 2009 at 16:34 UTC
You mean just `BEGIN`, not `sub BEGIN`. You're also missing a semicolon after `package foo`. You should be naming your package files with extension `.pm`, not `.pl`. You also don't need to specify the extension when `require`- or `use`-ing. You define `subroutine` in package `foo`, but try to use the `subroutine` from `package1`. The biggest one: The behaviour you describe has nothing to do with `BEGIN`. It works just the same if you remove the `BEGIN {}` block. UPDATE: AnomalousMonk points out (indirectly) that my point (4) is “only just” correct—the very early initialisation provided by `BEGIN {}` can certainly be useful if you might call a subroutine before some variables in it would be initialised by the normal flow of code.	[reply] [d/l] [select]
Re^3: BEGIN { } block by biohisham (Priest) on Aug 07, 2009 at 16:55 UTC
Thanks for the tips, I have taken due action, and your clarification is appreciated, as for note number 4 , I was seeking simplicity by showing a behavior that is relatively easier to correlate with and that is general, What I have presented has to do more with Packages, just to show one side of the many places BEGIN{} can come in handy and it just shows where BEGIN{} block can feature in a Package... Excellence is an Endeavor of Persistence. Chance Favors a Prepared Mind	[reply] [d/l]