Golang遮蔽行为解释[重复]

Question

This question already has an answer here:

• Golang mixed assignation and declaration 3 answers

In this snippet

    list := []string{"a", "b", "c"}
    for {
        list := repeat(list)
...

    func repeat(list []string) []string {
...

it is clear that list variable used as the argument to repeat() function is the outer, shadowed list variable. Now my question is, how would a Go language lawyer explain this behaviour? At first glance, I thought the declaration of the inner list variable would have preceded the repeat(list) expression evaluation.

</div>

Answer 1

Go is lexically scoped using blocks. In this example:

list := []string{"a", "b", "c"}
for {
    list := repeat(list)

The second list shadows the first within the for block, and doesn't alter the outer list variable.

Because the arguments to repeat are evaluated before the inner list is declared and assigned, repeat receives the value from the outer list