# V8035\. Type assertion is always false\. Check interfaces used in the type assertion, as they contain methods with incompatible signatures\.

The analyzer has detected a type assertion that can never succeed because both interfaces contain a method with the same name but different signatures\.

The example:

```cpp
type Validator interface {
  Validate() error
}

type ContextValidator interface {
  Validate(map[string]string) error
}

func check(v Validator) {
  ....
  if cv, ok = v.(ContextValidator); ok {
    ....
  }
  ....
}
```

In the example, the `v.(ContextValidator)` assertion cannot be true because the `Validate` method has different signatures in the `Validator` and `ContextValidator` interfaces\.

Such a type assertion would only make sense if the signatures of the `Validate` method are identical:

```cpp
type Validator interface {
  Validate() error
}

type ContextValidator interface {
  Validate() error
}
```