Why Do Go Concurrency Loops with Anonymous Functions Print the Same Value?

Understanding the Unexpected Behavior of Go Concurrency with For Loops and Anonymous Functions

In Go, when using a for loop to create goroutines with anonymous functions, an unexpected behavior can arise, resulting in all goroutines printing the same value. To comprehend this behavior, let's analyze the following code:

func main() {
    var wg sync.WaitGroup

    for i := 1; i <p>Surprisingly, this code prints "6, 6, 6, 6, 6," instead of the expected "2, 4, 1, 5, 3." This anomaly is attributed to the closures created by anonymous functions.</p><p>In Go, closures are functions that capture variables from their surrounding scope. In the code above, each anonymous function captures the variable i. However, when the for loop iterates, i is already at 5. This means that all the closures capture the same value of i, which is 6.</p><p>To solve this issue, we can pass i as an argument to the anonymous function. By doing so, we create a local copy of i that is captured by each closure, ensuring that each goroutine prints the correct value:</p><pre class="brush:php;toolbar:false">func main() {
    var wg sync.WaitGroup

    for i := 1; i 

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