So I added this to the columnSource.Rule and created a new set of rules for string functions in T-SQL:
columnSource.Rule = aggregate | stringFunction | Id;
stringFunction.Rule = stringFunctionName + "(" + stringFunctionArg + ")";
stringFunctionArg.Rule = term + "," + number;
stringFunctionName.Rule = COUNT | "Difference" | "Left" | "Right";
When I run the Irony Grammar Explorer, I can Parse my sample query but I notice that I am getting a Grammar Error of level "Conflict":
"Reduce-reduce conflict. State S50, lookaheads: (. Selected reduce on first production in conflict set."
I am not sure what I need to do to fix this? Any advice?