How about using the - magic file to tell Perl to read the script from STDIN? This saves you the __END__, and you can keep the -M5.012 to enable features:

perl -M5.012 -
    use strict;
    use warnings;
    use feature "declared_refs";
    no warnings "experimental::declared_refs";
    say ref my \$scalar;
    say ref my \@array;
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You need to press ^Z on Windows and ^D on unixish OSes to end your input though.