forwarding arguments to a constructor to a new function

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

I have a class that subclasses a base class with a custom constructor object.

My problem lay in that I want to share an generic init function (_init) called from new that will process common arguments passed to the constructor. Passing the args in @_ is easy to do - i'm just trying to figure out the best way to do it, and I'm unsure of how perl treats @_.

Should I devise a way to reference/de-reference @_ when it is passed/accessed? Is that completely unnecessary? I doubt I will be tossing large amounts of data around, but in the case that I do, I don't want to be needlessly copying variables all over when a simple reference will do.

Perhaps this will explain things better:

package Framework::myPackage ;
sub _init
{
my $this = shift; # shift off the ref in $_[0] so we can access the pa
+rams as @_
my %param = @_;
#or my %param = $@_; # do i want something like that (i know thats not
+ real perl)
}

package MyApp::myPackage ;
sub new
{
 ...
 $this->_init( @_ );
 #or  $this->_init( \@_ ); #?
}
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Comment on forwarding arguments to a constructor to a new function Download Code

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Re: forwarding arguments to a constructor to a new function by friedo (Prior) on Dec 21, 2005 at 05:28 UTC
Your first instinct was correct in both cases. To get named arguments out of the argument array, use `my %params = @_;`. To pass the arguments to another method in your constructor, do `sub new { my $this = shift; $this->_init( @_ ); }` [download] It doesn't really matter, but Perl convention is to use `$self` instead of `$this`. It's worth using if you ever plan to have other Perl people look at your code.	[reply] [d/l] [select]
Re: forwarding arguments to a constructor to a new function by blazar (Canon) on Dec 21, 2005 at 11:05 UTC
I see no particular reason to do ref/de-ref madness in this simple case. You would just be doing something only to undo it later: there's nothing in the way perl treats `@_` that would justify that.	[reply] [d/l]