Switch break statement

Technical Discussion
1

What benefit of break in switch statement? I mean labelled break is ok - for breaking outer loop. But simple break in switch is source of bugs, doesn’t it?

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2

In golang, there is no break for switch however for loops it is necessary.

3

Really?
Switch with simple break https://play.golang.org/p/LXKpdi2EHpm
Switch with labeled break https://play.golang.org/p/o0xh4tNl7x7

First example loops forever, second is breaking loop.

4

Well, what benefit depends on the code, but it breaks the switch and that can be useful.

switch {
	case something:
		foo, err := whatever()
		if err != nil {
			break
		}
		fmt.Println(foo)

	case somethingElse:
		// ...
	}
}

foo isn’t printed if an error occurs. I could also imagine it as the opposite of fallthrough.

switch {
	case something:
		// processing processing
		if notCommon {
               		break
		}
		fallthrough

	case somethingElse:
		// common stuff here
	}
}

The something case will continue into somethingElse unless notCommon is set. Making this too complicated is probably not a good idea, though.

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5

I agree with @calmh, though there may be other use cases, the most natural is probably error checking and breaking instead of going further in the case if there was indeed an error.

@Tanmay_Shirsath, please read the specs when you are not sure before answering with wrong statements. A quick search is enough to get something like this: https://golang.org/ref/spec#Break_statements. Also, try things in the playground to be sure. Here’s a slightly modified example of Go Tour that shows how unlabeled break would work in a switch statement: https://play.golang.org/p/Ta7Qov-7uRD.

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6

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