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Comment by dullgiulio | Hacker News Reader

You can easily access and modify the named return variables from a deferred function body.

If you had a variable declared in a block just before return, then you return it, you have no way to modify it in defer.

I personally don't like this style of code, but I can see some uses.

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Ok now I got they are in scope. About defer, could you think of it like defer makes a function into a function with multiple entry and exit points, possible to be stopped and resumed, like a coroutine?

Ehm, not sure I understood, but I'd say no. Defer is just code that is executed in reverse order upon return from a fuction. It has nothing to do with coroutines. It's a cleaner way to write the usual C syntax of "goto cleanup_x" code.

Go coroutines (goroutines) are functions invoked with the "go" keyword. These cannot be stopped or resumed, but might be (possibly) executed on a different thread. In any case, they are not guaranteed to be executed immediately in the normal flow of the code.

>Ehm, not sure I understood, but I'd say no. Defer is just code that is executed in reverse order upon return from a fuction.

I'd say more like the equivalent of a "finally" clause (or more) for your whole function.

Though not sure about the "executed in reverse order part" -- what's "in reverse order" about Defer? Except if you mean that multiple defers get executed "last seen first"...

Thanks alot for explaining, I think i get it a bit better now.

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