sagarpatel288

        /**
         * While calling the higher order function When the function type parameter is one and only parameter,
         * and if the function type has also one and only parameter,
         * in addition to function call parentheses, we can also omit the parameter of the function type and an arrow ```->```
         * We just write core business logic between curly braces
         * and we can access our single parameter through the keyword it like below:
         */
        doSomething { "$it" }

sagarpatel288

    //region A function type that has only one parameter
    private fun doSomething(ft: (Int) -> String) {
        /*...*/
    }
    //endregion

sagarpatel288

    //region A higher order function that has one and only function type parameter
    private fun doSomething(ft: (Int, Int) -> Int) {
        val result = ft(1, 2)
        /*...*/
    }
    //endregion

sagarpatel288

        /**
         * While calling the higher order function When the function type parameter is only parameter,
         * we can simply write our business logic between curly braces after writing the function name
         * and omit function call parentheses like below:
         */
        doSomething { x: Int, y: Int -> x + y }

sagarpatel288

fun Int.doSomething(y: Int, ftOne: Int.(Int) -> Int) {
        //passing a function type to another function
        val funOne = someFunction(ftOne)
        /*...*/
}

sagarpatel288

inline fun Int.doSomething(y: Int, noinline ftOne: Int.(Int) -> Int) {
        //passing a function type to another function
        val funOne = someFunction(ftOne)
        /*...*/
}

sagarpatel288

inline fun Int.doSomething(y: Int, noinline ftOne: Int.(Int) -> Int, ftTwo: (Int) -> Int) {
        //passing a function type to another function
        val funOne = someFunction(ftOne)
        /*...*/
}

sagarpatel288

//Compile time error… Illegal usage of inline function type [ftOne]...
inline fun Int.doSomething(y: Int, ftOne: Int.(Int) -> Int, ftTwo: (Int) -> Int) {
        //passing a function type to another function
        val funOne = someFunction(ftOne)
        /*...*/
}

sagarpatel288

inline fun Int.doSomething(y: Int, ftOne: Int.(Int) -> Int, ftTwo: (Int) -> Int) {
        /*...*/
}

sagarpatel288

fun Int.doSomething(y: Int, ftOne: Int.(Int) -> Int, ftTwo: (Int) -> Int) {
        /*...*/
}