private static CharSequence generateEnumFieldNotPresentCondition(
        final int sinceVersion, final String enumName, final String indent)
    {
        if (0 == sinceVersion)
        {
            return "";
        }

        return String.format(
            indent + "        if m.actingVersion < %1$d {\n" +
                indent + "            return %2$s_NULL_VALUE\n" +
                indent + "        }\n\n",
            sinceVersion,
            enumName);
    }
Create a new Golang language {@link CodeGenerator}.

@param ir                            for the messages and types.
@param shouldDecodeUnknownEnumValues generate support for unknown enum values when decoding.
@param outputManager                 for generating the codecs to.
sbe-tool/src/main/java/uk/co/real_logic/sbe/generation/golang/flyweight/GolangFlyweightGenerator.java