golang closure variable scope

Posted by waaadim on Stack Overflow See other posts from Stack Overflow or by waaadim
Published on 2013-11-13T15:12:28Z Indexed on 2013/11/13 15:54 UTC
Read the original article Hit count: 372

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go

|

closures

I'm reading 'CreateSpace An Introduction to Programming in Go 2012'

and on page 86 I found this evil magic

func makeEvenGenerator() func() uint {
    i := uint(0)

    return func() (ret uint) {
        ret = i
        i += 2
        return
    }
}

// here's how it's called
nextEven := makeEvenGenerator()
fmt.Println(nextEven())
fmt.Println(nextEven())
fmt.Println(nextEven())

1) Why is i not resetting ? 2) is nextEven() returning and uint or is Println so smart that it can work with everything ?

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