"Expression Expected"... what the heck?

So today some code that I haven’t changed in a while is suddenly throwing an error when I try to Build.

catch (ex) {
response.send(500, ex);

I retyped it manually thinking that maybe there’s a non-ASCII character or something, but no. I admit that I’m a weekend coder (aka newbie) but this has me stumped enough to post about it. Help?

Hard to say without seeing the whole program. What line is the error reported on? Maybe “response” is out of scope? Maybe the brackets got messed-up and the “catch” doesn’t correspond to a “try”?