Undeprecate find(predicate) and generate it for all collection-like types. Provide findLast(predicate).

Drop deprecated method findNot and extension properties first, last, head, tail
#KT-5185 Fixed

js/js.translator/testData/nameClashes/cases/extensionFunctionAndProperty.kt

@@ -1,14 +1,18 @@
 package foo
 
+public fun <T> List<T>.some(): T = this[0]
+public fun String.some(): Char = this[0]
+public val <T> List<T>.some: T get() = this[1]
+public val String.some: Char get() = this[1]
+
 fun box(): String {
 
     val data = listOf("foo", "bar")
 
-    assertEquals("bar", data.last())
-    assertEquals("bar", data.last)
-
-    assertEquals("foo", data.first)
-    assertEquals("foo", data.first())
+    assertEquals("foo", data.some())
+    assertEquals("bar", data.some)
+    assertEquals('f', "foo".some())
+    assertEquals('a', "bar".some)
 
     return "OK"
 }

libraries/stdlib/src/generated/_Elements.kt

@@ -806,6 +806,181 @@ public fun String.elementAtOrNull(index: Int): Char? {
     return if (index >= 0 && index <= lastIndex) get(index) else null
 }
 
+/**
+ * Returns the first element matching the given [predicate], or `null` if element was not found.
+ */
+public inline fun <T> Array<out T>.find(predicate: (T) -> Boolean): T? {
+    return firstOrNull(predicate)
+}
+
+/**
+ * Returns the first element matching the given [predicate], or `null` if element was not found.
+ */
+public inline fun BooleanArray.find(predicate: (Boolean) -> Boolean): Boolean? {
+    return firstOrNull(predicate)
+}
+
+/**
+ * Returns the first element matching the given [predicate], or `null` if element was not found.
+ */
+public inline fun ByteArray.find(predicate: (Byte) -> Boolean): Byte? {
+    return firstOrNull(predicate)
+}
+
+/**
+ * Returns the first element matching the given [predicate], or `null` if element was not found.
+ */
+public inline fun CharArray.find(predicate: (Char) -> Boolean): Char? {
+    return firstOrNull(predicate)
+}
+
+/**
+ * Returns the first element matching the given [predicate], or `null` if element was not found.
+ */
+public inline fun DoubleArray.find(predicate: (Double) -> Boolean): Double? {
+    return firstOrNull(predicate)
+}
+
+/**
+ * Returns the first element matching the given [predicate], or `null` if element was not found.
+ */
+public inline fun FloatArray.find(predicate: (Float) -> Boolean): Float? {
+    return firstOrNull(predicate)
+}
+
+/**
+ * Returns the first element matching the given [predicate], or `null` if element was not found.
+ */
+public inline fun IntArray.find(predicate: (Int) -> Boolean): Int? {
+    return firstOrNull(predicate)
+}
+
+/**
+ * Returns the first element matching the given [predicate], or `null` if element was not found.
+ */
+public inline fun LongArray.find(predicate: (Long) -> Boolean): Long? {
+    return firstOrNull(predicate)
+}
+
+/**
+ * Returns the first element matching the given [predicate], or `null` if element was not found.
+ */
+public inline fun ShortArray.find(predicate: (Short) -> Boolean): Short? {
+    return firstOrNull(predicate)
+}
+
+/**
+ * Returns the first element matching the given [predicate], or `null` if element was not found.
+ */
+public inline fun <T> Iterable<T>.find(predicate: (T) -> Boolean): T? {
+    return firstOrNull(predicate)
+}
+
+/**
+ * Returns the first element matching the given [predicate], or `null` if element was not found.
+ */
+public inline fun <T> Sequence<T>.find(predicate: (T) -> Boolean): T? {
+    return firstOrNull(predicate)
+}
+
+/**
+ * Returns the first character matching the given [predicate], or `null` if character was not found.
+ */
+public inline fun String.find(predicate: (Char) -> Boolean): Char? {
+    return firstOrNull(predicate)
+}
+
+/**
+ * Returns the last element matching the given [predicate], or `null` if no such element was found.
+ */
+public inline fun <T> Array<out T>.findLast(predicate: (T) -> Boolean): T? {
+    return lastOrNull(predicate)
+}
+
+/**
+ * Returns the last element matching the given [predicate], or `null` if no such element was found.
+ */
+public inline fun BooleanArray.findLast(predicate: (Boolean) -> Boolean): Boolean? {
+    return lastOrNull(predicate)
+}
+
+/**
+ * Returns the last element matching the given [predicate], or `null` if no such element was found.
+ */
+public inline fun ByteArray.findLast(predicate: (Byte) -> Boolean): Byte? {
+    return lastOrNull(predicate)
+}
+
+/**
+ * Returns the last element matching the given [predicate], or `null` if no such element was found.
+ */
+public inline fun CharArray.findLast(predicate: (Char) -> Boolean): Char? {
+    return lastOrNull(predicate)
+}
+
+/**
+ * Returns the last element matching the given [predicate], or `null` if no such element was found.
+ */
+public inline fun DoubleArray.findLast(predicate: (Double) -> Boolean): Double? {
+    return lastOrNull(predicate)
+}
+
+/**
+ * Returns the last element matching the given [predicate], or `null` if no such element was found.
+ */
+public inline fun FloatArray.findLast(predicate: (Float) -> Boolean): Float? {
+    return lastOrNull(predicate)
+}
+
+/**
+ * Returns the last element matching the given [predicate], or `null` if no such element was found.
+ */
+public inline fun IntArray.findLast(predicate: (Int) -> Boolean): Int? {
+    return lastOrNull(predicate)
+}
+
+/**
+ * Returns the last element matching the given [predicate], or `null` if no such element was found.
+ */
+public inline fun LongArray.findLast(predicate: (Long) -> Boolean): Long? {
+    return lastOrNull(predicate)
+}
+
+/**
+ * Returns the last element matching the given [predicate], or `null` if no such element was found.
+ */
+public inline fun ShortArray.findLast(predicate: (Short) -> Boolean): Short? {
+    return lastOrNull(predicate)
+}
+
+/**
+ * Returns the last element matching the given [predicate], or `null` if no such element was found.
+ */
+public inline fun <T> Iterable<T>.findLast(predicate: (T) -> Boolean): T? {
+    return lastOrNull(predicate)
+}
+
+/**
+ * Returns the last element matching the given [predicate], or `null` if no such element was found.
+ */
+public inline fun <T> List<T>.findLast(predicate: (T) -> Boolean): T? {
+    return lastOrNull(predicate)
+}
+
+/**
+ * Returns the last element matching the given [predicate], or `null` if no such element was found.
+ */
+public inline fun <T> Sequence<T>.findLast(predicate: (T) -> Boolean): T? {
+    return lastOrNull(predicate)
+}
+
+/**
+ * Returns the last character matching the given [predicate], or `null` if no such character was found.
+ */
+public inline fun String.findLast(predicate: (Char) -> Boolean): Char? {
+    return lastOrNull(predicate)
+}
+
 /**
  * Returns first element.
  * @throws [NoSuchElementException] if the collection is empty.

libraries/stdlib/src/kotlin/deprecated/Deprecated.kt

@@ -2,12 +2,6 @@ package kotlin
 
 import java.util.*
 
-deprecated("Use firstOrNull function instead.", ReplaceWith("firstOrNull(predicate)"))
-public inline fun <T> Array<out T>.find(predicate: (T) -> Boolean): T? = firstOrNull(predicate)
-
-deprecated("Use firstOrNull function instead.", ReplaceWith("firstOrNull(predicate)"))
-public inline fun <T> Iterable<T>.find(predicate: (T) -> Boolean): T? = firstOrNull(predicate)
-
 deprecated("Use listOf(...) or arrayListOf(...) instead", ReplaceWith("arrayListOf(*values)"))
 public fun arrayList<T>(vararg values: T): ArrayList<T> = arrayListOf(*values)
 
@@ -27,27 +21,6 @@ public fun <K, V> linkedMap(vararg values: Pair<K, V>): LinkedHashMap<K, V> = li
 deprecated("Use toList() instead.", ReplaceWith("toList()"))
 public fun String.toCollection(): Collection<Char> = toCollection(ArrayList<Char>(this.length()))
 
-/**
- * Returns the first character which matches the given *predicate* or *null* if none matched
- *
- * @includeFunctionBody ../../test/text/StringTest.kt find
- */
-deprecated("Use firstOrNull instead", ReplaceWith("firstOrNull(predicate)"))
-public inline fun String.find(predicate: (Char) -> Boolean): Char? {
-    for (c in this) if (predicate(c)) return c
-    return null
-}
-
-/**
- * Returns the first character which does not match the given *predicate* or *null* if none matched
- *
- * @includeFunctionBody ../../test/text/StringTest.kt findNot
- */
-deprecated("Use firstOrNull instead with negated predicate")
-public inline fun String.findNot(predicate: (Char) -> Boolean): Char? {
-    for (c in this) if (!predicate(c)) return c
-    return null
-}
 
 /**
  * A helper method for creating a [[Runnable]] from a function
@@ -101,49 +74,6 @@ deprecated("Use compareValuesBy() instead", ReplaceWith("compareValuesBy(a, b, *
 public fun <T : Any> compareBy(a: T?, b: T?, vararg functions: (T) -> Comparable<*>?): Int = compareValuesBy(a, b, *functions)
 
 
-/**
- * Returns the first item in the list or null if the list is empty
- *
- * @includeFunctionBody ../../test/collections/ListSpecificTest.kt first
- */
-deprecated("Use firstOrNull() function instead", ReplaceWith("this.firstOrNull()"))
-public val <T> List<T>.first: T?
-    get() = this.firstOrNull()
-
-
-/**
- * Returns the last item in the list or null if the list is empty
- *
- * @includeFunctionBody ../../test/collections/ListSpecificTest.kt last
- */
-deprecated("Use lastOrNull() function instead", ReplaceWith("this.lastOrNull()"))
-public val <T> List<T>.last: T?
-    get() {
-        val s = this.size()
-        return if (s > 0) this[s - 1] else null
-    }
-
-
-/**
- * Returns the first item in the list or null if the list is empty
- *
- * @includeFunctionBody ../../test/collections/ListSpecificTest.kt head
- */
-deprecated("Use firstOrNull() function instead", ReplaceWith("firstOrNull()"))
-public val <T> List<T>.head: T?
-    get() = firstOrNull()
-
-/**
- * Returns all elements in this collection apart from the first one
- *
- * @includeFunctionBody ../../test/collections/ListSpecificTest.kt tail
- */
-deprecated("Use drop(1) function call instead", ReplaceWith("drop(1)"))
-public val <T> List<T>.tail: List<T>
-    get() {
-        return drop(1)
-    }
-
 /** Returns true if this collection is empty */
 deprecated("Use isEmpty() function call instead", ReplaceWith("isEmpty()"))
 public val Collection<*>.empty: Boolean

libraries/tools/kotlin-stdlib-gen/src/templates/Elements.kt

@@ -398,6 +398,14 @@ fun elements(): List<GenericFunction> {
         }
     }
 
+    templates add f("find(predicate: (T) -> Boolean)") {
+        inline(true)
+        doc { "Returns the first element matching the given [predicate], or `null` if element was not found." }
+        doc(Strings) { "Returns the first character matching the given [predicate], or `null` if character was not found." }
+        returns("T?")
+        body { "return firstOrNull(predicate)"}
+    }
+
     templates add f("last()") {
         doc { """Returns the last element.
         @throws [NoSuchElementException] if the collection is empty.""" }
@@ -584,6 +592,15 @@ fun elements(): List<GenericFunction> {
         }
     }
 
+    templates add f("findLast(predicate: (T) -> Boolean)") {
+        inline(true)
+        include(Lists)
+        doc { "Returns the last element matching the given [predicate], or `null` if no such element was found." }
+        doc(Strings) { "Returns the last character matching the given [predicate], or `null` if no such character was found." }
+        returns("T?")
+        body { "return lastOrNull(predicate)"}
+    }
+
     templates add f("single()") {
         doc { "Returns the single element, or throws an exception if the collection is empty or has more than one element." }
         doc(Strings) { "Returns the single character, or throws an exception if the string is empty or has more than one character." }