alt Hacker NewsClosing the channel is pointless. I don't understand why people get obsessive about closing channels.
It's not needed by the garbage collector, it's not good practice. It's explicitly called out in the official go guide as unnecessary most of the time. [0]
If you have a channel that is only used a single time and then discarded, closing it is literally just wasting CPU cycles. And definitely not "lazy/rude".
I illustrated why closing the channel is beneficial: the consumer of the channel may not be using it properly. Reading the unclosed channel more than once will hang. A stuck goroutine is rarely desirable. The cost of closing a channel is similar to the cost of bounds checking; it may not be free, but it's usually worth it. Agreed that this has no benefit to the garbage collector. I also think this is a pretty clear example of when you should close a channel, as pointed out by the Tour: to inform the consumer that no more values will ever be forthcoming.