presto-spi/src/main/java/io/prestosql/spi/type/QuantileDigestParametricType.java/QuantileDigestParametricType/createType
class QuantileDigestParametricType:    @Override
    public Type createType(TypeManager typeManager, List<TypeParameter> parameters)
    {
        checkArgument(parameters.size() == 1, "QDIGEST type expects exactly one type as a parameter, got %s", parameters);
        checkArgument(
                parameters.get(0).getKind() == ParameterKind.TYPE,
                "QDIGEST expects type as a parameter, got %s",
                parameters);
        // Validation check on the acceptable type (bigint, real, double) intentionally omitted
        // because this is validated in each function and to allow for consistent error messaging
        return new QuantileDigestType(parameters.get(0).getType());
    }