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Passing lambda to another function

Kotlin allows us to pass a function to other (higher-order) functions as a parameter, using the lambda expression. Such a function can accept as a parameter a lambda expression or an anonymous function. Before discussing this topic further, let us first understand what a function type is.

Kotlin is a statically typed language and the functions also need to have a type. It is called a function type. We will see a few examples of how to define them as follows:

• ()->Int: The function type that returns an integer type and takes no argument.
• (Int)->Unit: The function type that takes an integer parameter and returns nothing.
• ()->(Int)->String: The function type that returns another function, which eventually returns ...