In Arrow Optics, is there an equivalent of 'lift' ...

# arrow

[Luke]

In Arrow Optics, is there an equivalent of 'lift' but just to get the value? I have something like val getId: (MyClass) -> String? = MyClass.somePath.id::getOrNull, which works, but I would prefer to call a method instead of ::getOrNull to return a lambda directly so I don't have to explicit the variable type.

[simon.vergauwen]

Yes, all optics should have lift in their APIs.

https://arrow-kt.io/docs/apidocs/arrow-optics/arrow.optics/-p-lens/index.html

[Luke]

But lift generates a function to modify the source right? I want to generate a function to get the value in the source

[simon.vergauwen]

Oh I see. I'm sorry.

Then I think your best best would be to work with ::getOrNull. I'm not sure what you mean with to explicit the variable type.

Is it not simply returning (MyClass) -> String? ?

[Luke]

No, it returns a KFunction1<MyClass, String?>. I just assumed I couldn't use it as a lambda but I guess I can. Thanks for the help