Hi Peter,
Thank you very much,
Li
--- Peter Cornelius <[EMAIL PROTECTED]> wrote:
>
> On May 27, 2006, at 3:56 PM, chen li wrote:
> >
> > Based on what I learn the regular method to defer
> a
> > hash reference to get specific value takes this
> > format:
> >
> > $ref_hash->{key1}
> >
> > but in this line
> > $_[0]->{_name}= $_[1] if defined $_[1]
> >
> > the format is
> > array element->{_name}
> >
>
> Yes, the contents of the array element is a hash
> ref. You could
> rewrite this to be the equivalent
>
> ${$_[0]}->{_name} = $_[1] if defined $_[1]
>
> Using the '{}' around the $_[0] to more clearly mark
> it as a reference.
>
> > Is the middle man $ref_hash is omitted in this
> format?
> > Does this what Perl really sees:
> >
> > $_[0]=$ref_hash;
> >
> > $ref_hash->{_name};
> >
> > and put these two lines into one line to make it
> > short:
> >
> > $_[0]->{_name}
>
> It's not really omitted, rather the argument passed
> in was a hash
> reference so the first element of the array ($_[0])
> is a hash
> reference. You could alias it by saying
>
> $ref_hash = $_[0];
>
> or, if you're feeling confident use it without the
> alias, as in this
> example.
>
> I guess this hash reference is being implicitly
> passed in by the
> method call as part of Perl's OOP implementation so
> you never do see
> the actual parameter passage of
>
> name($ref_hash, $new_name)
>
> Is this what's confusing you?
>
> Hope this helps,
> PC
>
> --
> To unsubscribe, e-mail:
> [EMAIL PROTECTED]
> For additional commands, e-mail:
> [EMAIL PROTECTED]
> <http://learn.perl.org/>
> <http://learn.perl.org/first-response>
>
>
>
__________________________________________________
Do You Yahoo!?
Tired of spam? Yahoo! Mail has the best spam protection around
http://mail.yahoo.com
--
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]
<http://learn.perl.org/> <http://learn.perl.org/first-response>
