In your specific example you have at least two options:

  1. Rummage through package stashes and globs e.g 
    @Foo::ISA = qw(Hello World);

use strict;
use feature 'say';

my $class = 'Foo';
my $isa   = *{ $main::{"$class\::"}{ISA} }{ARRAY};

say "@$isa"; # Hello World

    [download]
  2. Use the core package Symbol and make use of qualify_to_ref e.g 
    @Foo::ISA = qw(Hello World);

use strict;
use feature 'say';
use Symbol 'qualify_to_ref';

my $class = 'Foo';
my $isa   = *{qualify_to_ref 'ISA', $class}{ARRAY};

say "@$isa"; # Hello World

    [download]
The former won't work with nested packages whereas the latter will.
HTH

_________
broquaint

In reply to Re: Symbolic reference with strict "refs" by broquaint
in thread Symbolic reference with strict "refs" by denishowe

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