Question: Maple Doesn't Recognize Function Definition?

Hey everyone. Another question. I am getting a bug I have never gotten before - it's really bizarre. I have a sheet that works perfectly fine. All the functions are defined normally and they work properly. Then, when I get to the bottom of the sheet and try to define

> pathZ(r,theta):=(1- Heaviside(theta-Pi/(12)))*centralR*theta+Heaviside(theta-Pi/(12))*(centralR*Pi)/(12);

I get nothing being defined. I press enter while at that line and then it just goes to the next line without outputting anything. I then try to evaluate that function, because maybe it just isn't displaying it, and I get

pathZ(1,2);

pathZ(1,2)

That is, it isn't holding that function in memory.

I will upload the sheet... but I really have no idea what's going on!

sec-bend-Bfield.mw