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Comment by slowmovintarget | Hacker News Reader

I recall avoiding multiple method exits (in Java) like the plague. They were hell to get through in a debugging session. But I guess we don't use debuggers much any more.

When I began writing C# I recall my other team members "refactoring" my code to be shot through with multiple exits instead of a my collecting variable, because "it looked nicer." When they asked me why I wrote it the way I did, I mentioned the Java debugger thing, and they kind of looked at me blankly and said, "Huh, never thought of that."

Times change.

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Why is multiple method exits hell to get through with a debugger? I use a debugger for my C++ code all the time and I’ve never run into an issue because of multiple returns.

Setting breakpoints to inspect local state means you have to catch every single exit. Back then, if you had a thirty second to one minute round trip to get back to the method you were inspecting, it became... frustrating. You probably didn't have to deal with those kind of start-up round trips in C++. With C++ you'd pay on the compile time.

If you wrote the code to have a single exit, the cognitive load was also typically lower, as the control flow could be thought of as one way in, and two ways out (return or exception). Good disciple also followed "the jolly good idea of Demeter" or whatever it came to be called; that being to only operate on the state (or preferably, values) passed in, where possible.

I know this is a late response, but this still doesn’t really make sense to me. What stopped you from placing the break point at the start of the function, before the return values were hit and stepping through the code?

In my experience, having multiple exits is even better because I can check which edge case is being hit by placing multiple breakpoints, or a breakpoint at a specific exit I want to check. I understand the pain of having to step through the code to get back to a certain execution point, but I’ve never been in a situation where multiple exits caused such cognitive load as to hinder that process further.

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