Why is the error sent to original channel can still be received after recreating the channel?

[Feng Liyuan (SunRunAway)]

I have a piece of Go code where I create a buffered error channel and send an error to it from a goroutine. Then, in the main, I recreate this channel. To my confusion, even after recreating the channel, I still receive the error sent by the original goroutine. Here is the code:

https://go.dev/play/p/y3roOPKO0iy

Can someone help explain why this happens?

[robert engels]

Because the channel is captured by reference, so when the Go routine runs it already has the later value.

Your code has a race condition - run it under the race detector.

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[Justin Israel]

On Friday, September 20, 2024 at 8:52:46 AM UTC+12 robert engels wrote:

Because the channel is captured by reference, so when the Go routine runs it already has the later value.

Maybe this modified version better illustrates the problem:
https://go.dev/play/p/XLekzv9wsVO

The original code has no synchronization, so you cannot be sure when the goroutine will run and reference the channel from the outer scope. This updated example shows the difference between synchronizing before and after the goroutine.