[Mono-devel-list] Do we really need ONLY_1_0 and ONLY_1_1?

[Atsushi Eno]

Hello,

I noticed that in mcs/class/README we suggest to use conditional
directive named ONLY_1_0 and ONLY_1_1 in the class libraries (and
actually used in System.Data), for members that are removed after
.NET 2.0.

	#if ONLY_1_0 || ONLY_1_1
	   ...
	#endif

But since our switches are applied accumulative (we don't use
-d:NET_2_0 without -d:NET_1_1), I would suggest to replace them like:

	#if NET_2_0
	  /* empty */
	#else
	   code body
	#endif

Then "-d:NET_1_1" will be sufficient for our build condition.

We had better provide better description on how to use those switches.
If based on the proposal above, it is like:

1) For members only after .NET Framework 1.1
	#if NET_1_1
	  code
	#endif

2) For members only after .NET Framework 2.0
	#if NET_2_0
	  code
	#endif

3) For members removed after .NET Framework 1.1
e.g. System.Xml.XmlTextReader.ReadInnerXml()
	#if NET_1_1
	  /* empty */
	#else
	  ...
	#endif

4) For members removed after .NET Framework 2.0
e.g. System.Data.FieldNameLookup

	#if NET_2_0
	  /* empty */
	#else
	  ...
	#endif

5) For members removed only in .NET Framework 1.1

	#if NET_2_0
	  new definition
	#elif NET_1_1
	  /* empty */
	#else
	  old definition
	#endif

This way does not premise that the case when .NET 1.0 and .NET 2.0
uses the common code, but it is unlikely to happen.

Thanks,
Atsushi Eno