The Difference Between let and var in JavaScript. In JavaScript, you can use let or var to declare mutable variables. A variable with the let keyword will only be used within the block it is declared and not affect variables used in nested blocks, like if statements and for loops, or outside the block. Below is an example: The other option is var. What is the difference between var and val in Kotlin? I have gone through this link: KotlinLang: Properties and Fields. As stated on this link: The full syntax of a read-only property declaration differs from a mutable one in two ways: it starts with val instead of var and does not allow a setter. But just before there is an example which uses There are three ways to declare a MutableState object in a composable: val mutableState = remember { mutableStateOf (default) } var value by remember { mutableStateOf (default) } val (value, setValue) = remember { mutableStateOf (default) } These declarations are equivalent, and are provided as syntax sugar for different uses of state. That would mean you're declaring ptr as follows: int **ptr; In this case: ptr is a pointer to the pointer to your variable. *ptr is the pointer to your variable. &ptr gives you the address of ptr, so a pointer to the pointer to the pointer to your variable. For example: In Kotlin, `val` ensures immutability, ideal for constants and configuration data, enhancing code safety and predictability. Using `var` provides necessary mutability for stateful objects and user input, balancing flexibility with careful state management. Immutability with `val` simplifies multi-threading, reducing side effects and concurrency To read more, check data-classes. About the result, Technically, you are getting is different because of implementation of toString () method. data class' toString () method uses data class properties and values to form returning string. General class' toString () method uses hash code to form returning string. Share. gW8Lop. 0. In very simple terms, use var or val in class constructor parameters when you want to use that variable, say, inside a method within that class. Thus you're effectively turning them into properties and not just mere constructor or method parameters. class User (var name: String, age: Int) { var str = "John" var num = 18 fun setName () { name Accordingly, the main difference between the two is that val declares an immutable variable (i.e., a variable that cannot be reassigned after it has been initialized). Whereas, var declares a mutable variable (i.e., a variable that can be reassigned). The following example shows their usage. val x = 10 // x is a val x = 20 // This will result C++ Pointers. Pointers are symbolic representations of addresses. They enable programs to simulate call-by-reference as well as to create and manipulate dynamic data structures. Iterating over elements in arrays or other data structures is one of the main use of pointers. The address of the variable you’re working with is assigned to the In Kotlin, val and var are keywords used to declare variables, and they have different meanings based on mutability. Variables declared with val are read-only or immutable. Once a value is a := 10 b := "gopher". a will be declared as an int and initialized with value 10 where as b will be declared as a string and initialized with value gopher. Their equivalents using = would be. var a = 10 var b = "gopher". = is assignment operator. It is used the same way you would use it in any other language.

difference between var and val