feat: enhanced filterIsInstance

Author: MukjepScarlet

buildSrc/src/main/kotlin/fastutil-ext-generator.gradle.kts

@@ -21,6 +21,7 @@ val generateAllTask = tasks.register("generate-all") {
         enumSetTask,
         enumMapTask,
         forEachIsInstanceTask,
+        filterIsInstanceToTask,
         functionInvokeTask,
         predicateInvokeTask,
         consumerInvokeTask,
@@ -797,6 +798,24 @@ val forEachIsInstanceTask = tasks.register<GenerateSrcTask>("forEachIsInstance")
     }
 }
 
+val filterIsInstanceToTask = tasks.register<GenerateSrcTask>("filterIsInstanceTo-enhanced") {
+    group = TASK_GROUP
+
+    packageName.set(PACKAGE)
+    imports.add("java.util.stream.Stream")
+
+    content {
+        for (receiver in arrayOf("Array<*>", "Iterable<*>", "Iterator<*>", "Sequence<*>", "Stream<*>")) {
+            appendLine("inline fun <reified R, C : MutableCollection<in R>> $receiver.filterIsInstanceTo(destination: C, predicate: (R) -> Boolean): C {")
+            appendLine("    for (element in this) {")
+            appendLine("        if (element is R && predicate(element)) destination.add(element)")
+            appendLine("    }")
+            appendLine("    return destination")
+            appendLine("}")
+        }
+    }
+}
+
 val functionInvokeTask = tasks.register<GenerateSrcTask>("function-invoke") {
     group = TASK_GROUP
 

fastutil4k-extensions-only/src/main/kotlin/filterIsInstance-enhanced.kt

@@ -0,0 +1,20 @@
+@file:Suppress("unused", "NOTHING_TO_INLINE")
+@file:JvmName("filterIsInstance-enhanced")
+package net.ccbluex.fastutil
+
+import java.util.function.Predicate
+import java.util.stream.Stream
+
+inline fun <reified R> Array<*>.filterIsInstance(predicate: (R) -> Boolean): List<R> =
+    filterIsInstanceTo(ArrayList(), predicate)
+
+inline fun <reified R> Iterable<*>.filterIsInstance(predicate: (R) -> Boolean): List<R> =
+    filterIsInstanceTo(ArrayList(), predicate)
+
+@Suppress("UNCHECKED_CAST")
+inline fun <reified R> Sequence<*>.filterIsInstance(crossinline predicate: (R) -> Boolean): Sequence<R> =
+    filter { it is R && predicate(it) } as Sequence<R>
+
+@Suppress("UNCHECKED_CAST")
+inline fun <reified R> Stream<*>.filterIsInstance(crossinline predicate: (R) -> Boolean): Stream<R> =
+    filter(Predicate { it is R && predicate(it) }) as Stream<R>