References came about mainly because
traditionally, Perl had a limited range of data structures
with which to manipulate data
Specifically, Perl supported simple,
linear data structures like list arrays, scalars, and hashes.
For most of the daily chores of programming, of course, this
However, from time to time, one might
need to use a more complex data structure like perhaps an array
of arrays. Well, complex data structure manipulation in Perl
turned out to be quite a pain in the butt. So when Perl 5 came
around, everyone was pleased to see the adoption of "references"
which were roughly similar to pointers from C or C++ and could be used
to help construct complex data structures.
Essentially, a reference holds a scalar value
representation of some portion in memory where some other Perl
objectís (scalars, arrays, hashes, subroutines, etc) value is
stored. Take a look at this depicted graphically:
As we discuss the syntax of references in the following
slides, we will begin to see how this simple idea has powerful