[Xotcl] xotcl::nonposArgs

[Stefan Sobernig]

Hi Michael!

>> What is the correct way to port this to XOTcl 2.0?

This is most likely not an authoritative answer, I don't have the time 
right now to think this through properly. The following should get you 
going for the time being:

if {[info command ::nx::methodParameterSlot] ne ""} {
     ::nx::methodParameterSlot object method type=sourced_guid {name 
value args} {
	if {![::nsf::is object $value] || [xotcl::Object info instances 
-closure $value] eq ""} {
	    error "'$value' is not an XOTcl object"
	}
	if {![$value istype ::foo::bar::SourcedGuid]} {
	    error "'$value' is not of type SourcedGuid but [$value info class]"
	}
     }
}

If you plan to co-maintain two code bases (one compatible with 1.6 and 
the other for 2+), then you might want to consider factoring out the 
value checker into a plain Tcl proc and forward/alias to this proc 
conditionally from ::xotcl::nonposArgs and ::nx::methodParameterSlot, 
respectively.

I leave this as an exercise to you ;)

Let me know whether the above works for you for the time being.

Cheers,
Stefan

P.S.: I suggest using "return -code error" in your value checker to skip 
one level on the callstack trace reported to the developer, to hide the 
details of the value checker in the reported trace.