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Milline on tühi liides ja nil väärtusega liides Go programmeerimiskeeles?

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Vastus AI-lt

In Go, the empty interface interface{} is an interface that contains no methods and can hold a value of any type. However, when a variable of interface type contains nil, it is important to understand exactly what nil means.

  • Empty interface, no value: a variable of interface type that does not point to any value is considered nil.
  • Interface with nil value: if the interface contains a specific type, but the value of that type is nil, then the interface itself is not equal to nil, because it contains information about the type.

Example:

var i interface{}       // i == nil
var p *int = nil         // p == nil
i = p                   // i != nil, because it contains the *int type, but the value is nil

fmt.Println(i == nil)   // false
fmt.Println(p == nil)   // true

It is important to consider this when checking for nil to avoid unexpected errors.