# or:  my $ref = "str$_";  # this is a purely symbolic reference, 
+access is the same as above
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I don't see how that is a symbolic reference? I think this is (had to think a while to come up with something contrived, here):

my $class = 'CGI';
my $version;
{
    no strict 'refs';
    $version = ${"${class}::VERSION"};
    use strict;
}
print $version # e.g. 3.05 on my machine
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In other words, we construct a variable's name ($CGI::VERSION) out of expanded variables ($class), and expand (it's almost like a string eval()) the result in turn to return the value stored under the constructed variable's name.

...mmmm still not really put elegantly, sorry.