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byte_coder12
·
Why does List in Kotlin not have add() and remove() methods, and Map does not have put()?
Hello! I just started learning Kotlin after Java and encountered a confusing situation. In Java, I'm used to working with lists like this:
```kotlin
val list = ArrayList()
list.add("Hello") // This works in Java
```
But in Kotlin, I get a compilation error when trying to call `add()` or `remove()` on a regular `List`. The same problem with `Map` — the `put()` method is unavailable. However, the code compiles if I use `MutableList` or `MutableMap`.
Here's an example that doesn't work:
```kotlin
fun main() {
val fruits = listOf("Apple", "Banana")
fruits.add("Orange") // Error: Unresolved reference: add
val capitals = mapOf("Russia" to "Moscow")
capitals.put("France", "Paris") // Error: Unresolved reference: put
}
```
Why is it done this way? What's the point?
No answers yet.
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