Task: Lambdas with Collections solved by ASMA, the Bonus will be comi…

lamda collections/lamda collections.iml

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+<?xml version="1.0" encoding="UTF-8"?>
+<module type="JAVA_MODULE" version="4">
+  <component name="NewModuleRootManager" inherit-compiler-output="true">
+    <exclude-output />
+    <content url="file://$MODULE_DIR$">
+      <sourceFolder url="file://$MODULE_DIR$/resources" type="java-resource" />
+      <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
+      <sourceFolder url="file://$MODULE_DIR$/test" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/testResources" type="java-test-resource" />
+    </content>
+    <orderEntry type="jdk" jdkName="openjdk-23" jdkType="JavaSDK" />
+    <orderEntry type="sourceFolder" forTests="false" />
+    <orderEntry type="library" name="KotlinJavaRuntime" level="project" />
+  </component>
+</module>

lamda collections/src/Main.kt

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+fun main() { //Is it a common practice to write all functions outside main function?
+    // and anything else (val,lists,..etc) inside main?
+    val numbersList = listOf(1,2,3,4,5,6,7,8,9,10)
+    val doubledNumbers = numbersList.map { it * 2 }
+    println(doubledNumbers)
+//
+    val names = listOf("Alice", "Bob", "Amir", "Charlie", "Annie", "David")
+    fun filterNames(names: List<String>, logic: (List<String>) -> List<String>): List<String> {
+        return logic(names)
+    }
+    val logic: (List<String>) -> List<String> = { namesList -> namesList.filter { it.startsWith("A") }}
+    println(filterNames(names, logic)) //Q? Can i do this in a simpler way? the question is stupidly written
+//
+    val words = listOf("apple", "banana", "kiwi", "strawberry", "grape")
+    val sorting = {list: List<String> -> list.sortedByDescending { it.length }} //Q! this one is used for any list?
+    //val sorting = words.sortedByDescending { it.length } // while this one is used for this specific list?
+    println(sorting(words))
+//
+    fun customFilter(numbers: List<Int>, filter: (Int) -> Boolean): List<Int> {
+    return numbers.filter(filter) }
+
+    // Instead of writing in-line Lambdas in the 2nd parameter, I can write full lambda funcions
+    // that I can use later on:
+    // val greaterThanFive: (Int) -> Boolean = { it > 5 }
+    //val evenNumbers: (Int) -> Boolean = { it % 2 == 0 }
+    // val multiplesOfThree: (Int) -> Boolean = { it % 3 == 0 }
+
+    println(customFilter(numbersList) { it > 5 })
+    println(customFilter(numbersList) { it % 2 == 0 })
+    println(customFilter(numbersList) { it % 3 == 0 })
+
+//
+    fun processNumbers(numbers: List<Int>): List<Int> {
+    val filterEven = { number: Int -> number % 2 !=0 }
+    val square = { number: Int -> number * number }
+    return numbers.filter(filterEven).map(square) }
+
+    println(processNumbers(numbersList))
+// BONUS
+    fun processNumbers2(numbers: List<Int>, filter: (Int) -> Boolean, square: (Int) -> Int): List<Int> {
+    return numbers.filter(filter).map(square)
+}
+    println(processNumbers2(numbersList, { it % 2 != 0}, { it * it }))
+}