Thanks, Chris and Wiggins!
- Bryan
> On Fri, 16 Dec 2005, Bryan R Harris wrote:
>
>> I remember from my C++ class that when you pass arguments to
>> subroutines you can pass them either as a pointer to the real variable
>> (so you modify the original if you change it), or as a copy (which you
>> can change all you want and not affect the original).
>
> The terminology I was taught for this was "pass by reference" to denote
> sending around pointers to the same physical memory location, and "pass
> by value" to denote sending around abstract logical pieces of
> information that are typically copies of the original variable.
>
> Like most languages, Perl has ways to do both of these.
>
> Normal argument passing in Perl is basically like pass by value or pass
> by copy. You don't generally have to do anything extra to get this
> behavior.
>
> To pass a reference to a variable to a subroutine, prefix the variable
> name with a backslash: \%myhash, [EMAIL PROTECTED], etc. You can capture this
> reference into a scalar -- $hashref = \%myhash -- and then access the
> contents of the reference by dereferencing: $$hashref{"KEY"} = "VALUE";
>
> This is explained in detail in perldoc's perlref and perlobj pages:
>
> http://perldoc.perl.org/perlref.html
> http://perldoc.perl.org/perlobj.html
>
> It's also in books like _Learning Perl Objects, References & Modules_
> and _Object Oriented Perl_:
>
> http://www.oreilly.com/catalog/lrnperlorm/
> http://www.amazon.com/exec/obidos/tg/detail/-/0596004788?v=glance
> http://books.perl.org/book/200
>
> http://www.manning.com/Conway/
> http://www.amazon.com/exec/obidos/tg/detail/-/1884777791?v=glance
> http://books.perl.org/book/171
>
>
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