I didn't know we have state variables now. I've been away reeeally long =)

use Text::CSV;
use feature 'state';

sub split_array_str ($value)
{
    state $csv = Text::CSV->new ({ sep_char => ",", quote_char => '"',
+ allow_whitespace => 1 });
    return $csv->parse( substr($value,1,-1) ) ?
        [$csv->fields] :
        $value;
}
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