Compile early and compile often

I’ve been writing a big and complicated program for a while. I’m not sure if it is supposed to be big and complicated, it just seems to be turning out that way. And one of the things I’ve remembered from my days of doing this kind of thing is “compile early and compile often”. If you wait a while before hitting the compile button you can sometimes get so many errors that it can take you a while to figure out. Modern editors are quite good at spotting coding mistakes as you write, but there is nothing like letting the compiler take a proper look at your code.

I’ve been hitting compile every time I’ve written a few lines. That way, if I get an error I don’t have to look through much text. I do this even though I’ve no intention of running the program at that stage. It’s just that when I’ve done a bit that I think should compile it is worth getting the proper opinion on the matter.

When I was teaching programming we used to get people come in with 500 line programs that didn’t compile and they weren’t sure why. They’d written all the code down and then hit compile and were surprised by the number of errors they got. I used to tell them that a good way to start would be with an empty program that compiles and then add the statements a small amount at a time, compiling at each stage.