calling a subroutine while Initializing new

opensourcer has asked for the wisdom of the Perl Monks concerning the following question:

hi,

i'm creating new instance like this:

my $instance = new MYPACKAGE(READ_ONLY => 1, \&subroutine);
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could any 1 explain where the subroutine in defined, i mean in the same program or in package called MYPACKAGE. if possible with example plz.

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Re: calling a subroutine while Initializing new by chromatic (Archbishop) on Sep 17, 2006 at 02:49 UTC
Which subroutine? If you're talking about the constructor `new()`, it should be in `MYPACKAGE`. (I say "should be" because with the syntax you're using there, a lot of weird things could happen. I recommend instead `my $instance = MYPACKAGE->new( READ_ONLY => 1, \&subroutine );`.) If you're talking about `subroutine()`, it depends. The only necessary condition is that there is a subroutine of that name in the current package. However it is in that package, whether by declaration or export or `AUTOLOAD` or installation into the symbol table otherwise, it just has to be there.	[reply] [d/l] [select]
Re: calling a subroutine while Initializing new by jkeenan1 (Deacon) on Sep 17, 2006 at 02:55 UTC
Most typically, you would define the subroutine in the package where the constructor is being called -- probably `package main;`. Note: for the most part, Perl classes, modules and packages (with the exception of `main`) are generally spelled in upper and lower case: `MyPackage` or `My::Package` -- not in all upper case. Jim Keenan	[reply] [d/l] [select]
Re: calling a subroutine while Initializing new by neosamuri (Friar) on Sep 17, 2006 at 03:06 UTC
If you are passing wanting to pass the subroutine to the module(as you are doing above), then the subrutine should be defined in the file that instantiates the object. If you are not wanting to pass the subroutine in to the module, then it should be in the package file and called from the new subroutine.	[reply]