I have a class
open class Texture and I'd like to define the equals(other: Texture) operator
operator fun equals(other: Texture) = ...
but I get
Error:(129, 5) Kotlin: 'operator' modifier is inapplicable on this function: must override ''equals()'' in Any
What does it mean?
If I change that to
operator fun equals(other: Any) = ...
Accidental override, two declarations have the same jvm signature
The equals() operator function is defined in Any, so it should be overriden with a compatible signature: its parameter other should be of type Any?, and its return value should be Boolean or its subtype (it's final):
open class Texture { // ... override operator fun equals(other: Any?): Boolean { ... } } Without the override modifier, your function will clash with the Any::equals, hence the accidental override. Also, equals() cannot be an extension (just like toString()), and it cannot be overriden in an interface.
In IntelliJ IDEA, you can use Ctrl+O to override a member, or Ctrl+Insert to generate equals()+hashCode()
false when other is not an instance of Texture?
if (other == null || other !is Texture) return false