Restricted variable names?

[Acetone]

Hello, 
I had a strange issue with my sequence. 
I used two global string variables named "CurrX" and "CurrY". These were intended to dynamically specify X and Y expressions for graph traces. However, the sequence just wouldn't work, the traces would be added (as seen in the graph properties; no actual trace appeared on the graph), but both expressions would be shown as "NaN". When I tried seeing the current value of these variables (typing "?CurrX" in the command line), it would return the "NaN" value as well. 
As best as I could figure, everything else in the sequence was working as intended. Rather frustrated, I just replaced every instance of the "CurrX" by a different word, which should probably not be repeated here - and it fixed the issue. Same with "CurrY". 

As far as I've searched the user's guide, there's no mention of variable names beginning with "Curr" causing any problems - indeed, some of the examples therein use "current" as a variable name. Is there any reason why "CurrX" and "CurrY" cannot be used, and if so, is there a comprehensive list of any other reserved/unavailable variable names?

[AzeoTech]

My guess is what you did is declared currX and currY as numerical variables first, i.e.:

global currX

then realized your error and fixed it to:

global string currX

The problem is that once a variable is declared, you can't redeclare it as a different type.  Thus you get NaN because you are assigning some string to currX and currY that can't be converted to a number, like "x + y".  If you happened to set it to "3" or even "3 + 4", DAQFactory would convert the string into a number, 3 in both cases, since the string isn't evaluated, it is simply converted up to the first invalid character.

There are three ways around this:
1) use a different variable name
2) save, close and reload the doc
3) do:

clearGlobals()

which will erase all global variables and thus require redeclaration of all your globals.

Note that this behavior is a symptom of DAQFactory being a dynamic language that allows changes on the fly, and certain optimizations that go with it.  A compiled language of course would not have this issue.  That all said, I will admit that this one catches me rather often as I often forget to include the "string" in my declarations

 

[Acetone]

I see. Not declaring it as a string from the very beginning might be what happened, yeah. Thank you!