presto-parser/src/main/java/io/prestosql/sql/parser/AstBuilder.java/AstBuilder/visitArrayType
class AstBuilder:    @Override
    public Node visitArrayType(SqlBaseParser.ArrayTypeContext context)
    {
        if (context.INTEGER_VALUE() != null) {
            throw new UnsupportedOperationException("Explicit array size not supported");
        }

        return new GenericDataType(
                getLocation(context),
                new Identifier(getLocation(context.ARRAY()), context.ARRAY().getText(), false),
                ImmutableList.of(new TypeParameter((DataType) visit(context.type()))));
    }