presto-spi/src/main/java/io/prestosql/spi/type/TypeSignatureParameter.java/TypeSignatureParameter/isCalculated
class TypeSignatureParameter:    public boolean isCalculated()
    {
        switch (kind) {
            case TYPE:
                return getTypeSignature().isCalculated();
            case NAMED_TYPE:
                return getNamedTypeSignature().getTypeSignature().isCalculated();
            case LONG:
                return false;
            case VARIABLE:
                return true;
            default:
                throw new IllegalArgumentException("Unexpected parameter kind: " + kind);
        }
    }