Java Intersection Type - You MUST know this

[@viraj_shetty]

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[@amajor5460]

Useful info, thanks for sharing.
I generally prefer to avoid using the var keyword. I'm a bit old school and think explicitly declaring the types is a good practice so it is totally clear.
Here's how I would handle the scenario you mentioned at the end.
interface A extends X, Y {}
interface B extends A {
void b();
}
interface C extends A {
void c();
}
A result = switch(city) {
case "New York" -> new B() {};
default -> new C() {};
}

[@viraj_shetty]

Thanks ! You bring up some good points. The place where I usually use a var is when it improves readability without sacrificing clarity.
For example, below is fine. It reduces clutter.
var city = "New York"
var map = new HashMap
But avoid, something like
var city = methodCall();
For the last example - I created that example to show how JVM "infers" the type if we use var and how it generates the Intersection Type. I totally agree with your approach, if we have full control of the design.

[@nikiforovsansanich]

Thank you, it is useful information. I didn't know about this

[@viraj_shetty]

I am glad you like it !