Reflecting the name of 'this' in a Kotlin extension function

Question

Is there a way to get the name of 'this' in an extension function?

fun Boolean?.persist() {

   if (this == null) return   // Do Nothing

   val nameOfVariable:String = //get the name of the variable? 

   // Persist variable
   PreferenceManager.getDefaultSharedPreferences(context).edit().putBoolean(nameOfVariable, this).apply()

}

Your `Boolean` isn't a variable, it's an object. A reference to the object may be stored in zero, one, two, ten, or any other number of variables. — Marko Topolnik, Nov 23 '18 at 08:49

score 2 · Accepted Answer · answered Nov 23 '18 at 08:27

2

What you intend to do is not possible. You'd have to provide the nameOfVariable as a parameter. The extension function could be called on any value not being backed by a variable as well.

Delegated Properties could be an alternative for your needs.

answered Nov 23 '18 at 08:27

tynn

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score 1 · Answer 2 · answered Nov 23 '18 at 08:20

1

I think you can't do that. As workaround pass name as a parameter:

fun Boolean?.persist(name: String) {
    // ...
     PreferenceManager.getDefaultSharedPreferences(context).edit().putBoolean(name, this).apply()
}

answered Nov 23 '18 at 08:20

Sergio

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Reflecting the name of 'this' in a Kotlin extension function

2 Answers2