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Comment by ecshafer | Hacker News Reader

This looks like it could be a good change. Personally I think new point with { x = 1, y = 2, z = 3 } is much cleaner looking than say point.withX(1).withY(2).withZ(3). names params is generally something I like it languages though, so I might be biased here.

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This concerns me:

    Point newLoc = oldLoc with {
        x *= 2;
        y *= 2;
        z *= 2;
    };

It feels more like a mutable "Builder" class than a copy constructor. I guess the benefit is that you can do things like the above, instead of the following in Kotlin:

    val newLoc = oldLoc.copy(
        x = oldLoc.x * 2,
        y = oldLoc.y * 2,
        z = oldLoc.z * 2
    )

But in Kotlin it's more clear that oldLoc is immutable.

For what it's worth, in Kotlin you could also do the following:

  val newLoc = oldLoc.run { copy(x = x * 2, y = y * 2, z = z * 2) }

The syntax is definitely strange and not Java like, it doesn’t match any Java syntax I recall. Not a lambda, not a method call, not a keyword or even a static method

It should be 1 of the above. They also made the same weird new syntax choice with string template.

One of the most important things about a language is coherence and consistency. That’s why a language designer is a role/talent

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