* * Never equal to null: for any non-null value `x`, `x.equals(null)` should return false. Take your first steps programming in Kotlin, add images and text to your Android apps, and learn how to use classes, objects, and conditionals to create an interactive app for your users. * * Consistent: for any non-null values `x` and `y`, multiple invocations of `x.equals(y)` consistently return true or consistently return false, provided no information used in `equals` comparisons on the objects is modified. Web version 8 Swift Objective-C Kotlin+KTX Java Dart. This division of code increases the readability of code, reusability of code, and makes a program easy to manage. write some data about cities so we can look at different ways to read it back: Web version 9 More. Functions allow a program to break it into various small code blocks. * * Transitive: for any non-null values `x`, `y`, and `z`, if `x.equals(y)` returns true and `y.equals(z)` returns true, then `x.equals(z)` should return true. Functions in any programming language is a group of similar statements which is designated to perform a specific task. * * Symmetric: for any non-null values `x` and `y`, `x.equals(y)` should return true if and only if `y.equals(x)` returns true. Implementations must fulfil the following * requirements: * * * Reflexive: for any non-null value `x`, `x.equals(x)` should return true.

** * Indicates whether some other object is 'equal to' this one. All three functions are well-known functions which can be overridden in any class.

Kotlin any