Perl Typeglob

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Type Glob

If you prefix the name of a Perl variable with an '*', you can refer to ALL the Perl objects (scalars, arrays, filehandles, subroutines) which have that name

Called a type glob (since the * represents a $ or @ or %)

When a type glob is assigned to another type glob, object aliasing is set up.

It is recommended that type globs be used as lvalues only inside local(). Otherwise, you may clobber an existing variable!

 Ex:

         @x = (5, 6, 7);
         &sub1 (*x); 
                                   
         sub sub1
         {
           local (*array) = @_;

           # Now any references to @array in the subroutine
           #   are really references to the global array @x.
           # Be careful!  All objects with name x have been
           #   aliased.  References to $array inside the subroutine
           #   will reference a global $x; same with %array
           #   and %x.
           # But now any array operation (for example, push/pop)
           #   can be done on @array and the changes made to the
           #   global @x.
     
         }