How to create an "extension class"?

[socialguy]

I’ve a file with a bunch of top-level extension functions for JUnit 5 ExtensionContext. Currently I have to specify the receiver for each and every one of the functions, which is repetitive and boilerplate. Is there a way to “extension class” such that all methods in it automatically acquire the receiver declared on the class? Something like:

object ExtensionContext.ExtensionContextUtils {
    fun fn() {...} 
}

Caller:
extensionContext.fn()

[Wasabi375]

Might be nice to declare extension methods without repeating the type

Was looking at some extension methods and properties I had declared and saw something like this: fun SomeReallyLongTypeName.method1() { ... } fun SomeReallyLongTypeName.method2() { ... } val SomeReallyLongTypeName.property1: SomeType get() = // ... val SomeReallyLongTypeName.property2: SomeType get() = // ... And was thinking about the way Dart declares extension methods (Extension methods | Dart) and in Dart extensions are always declared in an extension block. So in Dart that would be: exte…