Trapped Variables

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Trapping variables in for loops

// Bad example: Trapping loop variable
var results []int

for i := 0; i < 5; i++ {
    go func() {
        results = append(results, i)
    }()
}

var results []int

for i := 0; i < 5; i++ {
    go func(i int) {
        results = append(results, i)
    }(i)
}

time.Sleep(time.Second)
fmt.Println("Results:", results) // Output is as expected