Is there any active development on inline classes?...

# announcements

[Paul Woitaschek]

Is there any active development on inline classes? I find the idea so handy but the implementation is so limited.
For example I like to use it for units: inline class Calories(val value : Double)

But now I lose all functionallity of double. If I for example want to sum, substract or divide calories, I need to re-implement these basic math functions ontop of the Calories class as operator fun plus etc.

[Ruckus]

I believe that's kind of the point. If you just want Calories to be another name for Double, you use a typealias.

[kunalsheth]

If you find declaring each function to be tedious, you can always use a UOM library: https://github.com/kunalsheth/units-of-measure

[Paul Woitaschek]

Typealias doesnt provide type safety

[Paul Woitaschek]

typealias Calories = Double
typealias Gram = Double

fun Calories.bmr() {

}

fun mistake(gram: Gram){
  gram.bmr()
}

[Ruckus]

Yes, that's exactly my point.

[dave08]

I wonder if inline class Calories(val value: Double) : Double by value would work...?

[hho]

Compiler says no:
Inline class cannot implement an interface by delegation

[Ruckus]

Also, Double is not an interface

[dave08]

True 🙃, it was just the idea... but even that doesn't work..