Glad to hear that System Defaults are working for them. My main gripe with that mechanism is how cumbersome Portal's UI is for making the setting in the right place. Added to that, it's just too easy for someone to adjust a setting directly, filing the new setting into the production class where it (a) overrides the System Default and (b) propagates when the class gets transferred.

Or provided you can read and understand ObjectScript you could set up our Serenji debugger and then replay a message, stepping through the INT code.

Maybe modify the simplified rule you showed above, so it includes only the first of the 3 constraints. Then repeat with only the second. Then with only the third. Does this pinpoint only one constraint failing? Or do all three fail independently?

What Ensemble version are you using?

As well as the suggestion of using a process-private global, Tim flags up an important point here. The $ORDER technique only enumerates public local variables.

Here's a sneaky way to use a NEWable and SETtable system variable to cache your "safe" variable name in:

 new $etrap
 set $etrap=";"_..GetNewVarName() ; semicolon prefix makes the $ETRAP into a valid line of code (i.e. a comment)
 set @$extract($etrap,2,*)=""
 set @$extract($etrap,2,*)=$order(@@$extract($etrap,2,*))

You need more than one "safe" variable? Use subscripts of the one you've grabbed:

 set @$extract($etrap,2,*)@(1)="Some more info I need to store"

I think your code is vulnerable to a <MAXSTRING> error in the case of records with a large number of long values.

How about this instead, which might be a bit faster too?

set crc = 0
for i=1:1:in {
 set crc = $zcrc($char(i#256)_in(i), 7, crc)
}
return crc

Prefixing the input string to each $zcrc call with a character derived from the argument position number is intended to prevent us getting an unchanged CRC in the event that a substring has been removed from the beginning of one argument and appended to the previous argument (or removed from the end of one argument and prepended to the next argument)

The #256 is probably overkill because (a) you might be on a Unicode instance of Caché and (b) it might not even be possible to pass more than 255 arguments to the method (I haven't investigated).

Deltanji Solo Edition would be an straightforward way of adding source control to the SAMPLES namespace, and it's free.

Now it becomes clear!

I had wondered if your requirement for "string" was that it contained only printable characters. In such a case one solution could be to base64-encode the result of $listbuild. On a Unicode instance of Caché you'd need to convert it to UTF8 first.

USER>s list=$lb($c(0),$c(1),"Hello",",","World")
 
USER>s printable=$system.Encryption.Base64Encode($zconvert(list,"O","UTF8"))
 
USER>w printable
AwEAAwEBBwFIZWxsbwMBLAcBV29ybGQ=
USER>s list2=$zconvert($system.Encryption.Base64Decode(printable),"I","UTF8")
 
USER>w list2=list
1
USER>w $a($li(list2,1))
0
USER>w $a($li(list2,2))
1
USER>w $li(list2,3)
Hello
USER>w $li(list2,4)
,
USER>w $li(list2,5)
World
USER>

Note that Base64Encode adds a CRLF after every 76 characters, so if you want to remove these from your "printable" you can either $TR(printable,$c(13,10)) or on 2015.2 or later you can pass a second argument to Base64Encode.

I don't understand what you mean by "until the list values may contain any set of characters".

Nor do I understand the purpose of the second line of your terminal transcript above. None of your subsequent lines do anything with your local variable called list

I found this answer interesting. A bit of browsing in the history at http://docs.intersystems.com/cache.html shows that the ability to disable an index arrived in 2013.1.