Stefan Bauwens

"appvTESTVAR"->Str1

.If the appvar doesn't exist...

!If GetCalc(Str1)->P
.(assuming you want a pointer in P)

.create it
GetCalc(Str1,2)->P
0->{P}r

End

.Notice that first command, "!If GetCalc(Str1)->P", sneakily puts a pointer in P if the appvar does exist, so you don't have to do something like this:

!If GetCalc(Str1)
GetCalc(Str1,2)
End
GetCalc(Str1)

.^^This is bad code

.Do the first block of code and you should be fine