Partial copy constructors

[suhtai]

This idea came up on Twitter:
https://twitter.com/D0Wind/status/1587986699434328065?t=fdl2Sy3QUoaGgHj3AGVmjA&s=19

We can create partial copy constructors where we leave non matching properties as extra parameters of the generated constructor.

[serras]

I have to say I'm not very fond of this; I think this is one of the cases in which explicitness wins over an annotation.

[serras]

For the record, this is the image from Twitter

[suhtai]

Ok, I think we have two concepts here:
A) ignoring properties that are present on the source type and not on the target.
B) adding extra parameters to the copy constructor when the target type has more than the source.

I just realized that there were these two things happening.

I'm not sure about A as there is a risk of information loss. However, I think B could be interesting as it's more explicit.

[jiaojing]

Write the following code every day is boring，
fun Person.asDTO(addr: String): PersonDTO = PersonDTO( name = this.name, age = this.age, addr = addr )

[TobiasSuhrborg]

Actually, I came here looking for that exact functionality and noticed too late, that it's not supported.
I think the assumption for Isomorphic copy constructors is, that the different classes are not identical, otherwise in most cases they wouldn't be needed.