The first 'main_package_vars' is in a BEGIN block because it is a duplicate of the one below it. I want to move the BEGIN block out of the package declaration and into the 'main' block.

Then I want to use the package_vars definition in 'main'. I.e. I started with a BEGIN block only in a package like this (which works, but doesn't work if I remove the BEGIN block as you seem(?) to be suggesting).

#!/usr/bin/perl  -w
use strict;
use feature ':5.10';

package MyPackage;
{
    BEGIN {
        sub package_vars {
            foreach(@_) {
                eval "sub $_ {
                    my \$p = shift;
                    \$p->{$_} = \$_[0] if \@_;
                    \$p->{$_};
                }"
            }
        }
    }

    package_vars( qw(one two three) );

    sub new {
        my $package=shift;
        my $parms=$_[0];
        
        my $this={};

        foreach(%$parms) {
            $this->{$_}=$parms->{$_};
        }

        bless $this, $package;
    }
}

package main;

my $p=new MyPackage({three => 3,});

$p->two(1);

printf "two=%d, three=%d\n",$p->two, $p->three;
[download]

Now I try moving the BEGIN block out of the package and into main (thus 'main_package_vars'), and import it's functionality into the local package.

That's the problem I'm trying to solve. How to have my subroutine definition for 'package_vars' in 'main', and use it from a package, like in this (which doesn't work because package_vars, isn't being 'called' in MyPackage, now that it's been moved to main).

#!/usr/bin/perl  -w
use strict;
use feature ':5.10';

BEGIN {
    sub package_vars {
        foreach(@_) {
            eval "sub $_ {
                my \$p = shift;
                \$p->{$_} = \$_[0] if \@_;
                \$p->{$_};
            }"
        }
    }
}


package MyPackage;
    *package_vars=\&main::package_vars;
{

    package_vars( qw(one two three) );

    sub new {
        my $package=shift;
        my $parms=$_[0];
        
        my $this={};

        foreach(%$parms) {
            $this->{$_}=$parms->{$_};
        }

        bless $this, $package;
    }
}

package main;

my $p=new MyPackage({three => 3,});

$p->two(1);

printf "two=%d, three=%d\n",$p->two, $p->three;
[download]

The first version I posted had samples of the routine package_vars in each location where I could try changing the line that says 'package_vars3( qw(one two three));' to a line without the '3', and, call the original working version, vs. attempts at trying some way to call the version of 'package_vars' that was moved to main.

Is that more clear?