Hello, I have a question on using type globs. Namley, how does one use a typeglob and restrict the scope of the name mapping to a local scope. Apparently you cannot typeglob into a lexical variable.

longer explanation of the problem:

Those familiar with type globs will recognize the following conventional use:

@foo = ("initial");
*bar = \@foo;
$bar[0] = "final";
print @foo;
[download]

this will print "final".

this inserts the referent to @foo into the array slot of the typeglob of bar, and thus @bar and @foo are refer to the same memory. thus the result

So far so good. Now I got into trouble here when I tried to use in combination with "strict vars", and incidentaly inside of a package.

Strict requires that I declare the variable @bar, and as near as I can tell there are three ways I can do this. "my @bar;" or "our @bar;" or "use vars qw/@bar/;" using "my @bar;" causes the incorrect, or rather unintended result, because as near as I can tell you cannot typeglob a lexical variable. What appears to happen is that the type glob creates a package variable @bar and links it to @foo, but then this variable is not accessible anymore as @bar since it is masked by the previously declared lexical variable. Thus the assingment $bar[0]=1 goes into the lexical @bar and not into @foo.

my  @foo = ("initial");
use strict;
my @bar;
*bar = \@foo;
$bar[0] = "final";
print @foo;
[download]

this prints "Initial"

using "our @bar;" does achieve the desired outcome of printing "final" and making @bar and @foo linked. However, it does so apparently at the cost of creating a package global variable rather than a locally scoped variable. So the question is how do I get a locally scoped variable, and use a type glob? Actual use example of what I'm trying to do:

package wombat;

our @bar = ("haha");  # this is going to get
                      # accidentally clobbered

use strict;

sub A1 { 
     my @foo  = (1,2,3,4);
    
     return B2(3,\@foo);  # pass in reference to @foo
}

sub B2 {
     my ($n,$foo) = @_;
     
     # now instead of always indexing $foo as a reference,
     # I will use a type glob
     # to allow me to access it as though it were an array.
     # @bar here is intended to be just a temporary convenience
     # variable name.  But it accidentally collides with 
     # a package global used elsewhere.

     # my @bar;  # cannot do this, which would logically 
                 # be locally scoped as I want it to be
                 # and avoid stepping on package globals.
     
     our @bar;   # must do this instead, which because of 
                 #an accidental name collision with the 
                 # package global that is also  called
                 #  "@bar", is going to have a sideeffect.
     
 
     *bar = $foo;
     # now do something with @bar
     # --this is just a trivial placeholder process

      @bar = map { sin($n+$_) } @bar;
      

     return $bar[0]+$bar[4];  # just a trivial placholder
}

print A1();  # prints the expected result

print @bar;  # but @bar is no longer "haha".
             # because it gets clobbered because
             # I could not control the scope of the typeglob
[download]

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