Can you explain what a run {} code block is in programming language?

In Kotlin, the run {} block is a standard higher-order function that takes a lambda expression and executes it, returning the result of the last expression inside the block.

It is often used to perform multiple operations in the context of an object or to limit the scope of variables.

Example usage:

val result = run {
    val x = 10
    val y = 20
    x + y  // result of the block
}
println(result) // Will print 30

run is also used for calling methods on an object and returning the result:

val text = "Hello"
val length = text.run {
    println(this)  // Hello
    length  // return length of the string
}
println(length)  // 5

Thus, run helps structure code, limit variable scope, and return computation results inside the block.