Create method Collection.randomOrNull() #KT-35347

2020-01-15 22:16:47 +03:00
parent 80d5723a07
commit 3cad1bbb51
12 changed files with 589 additions and 0 deletions
@@ -2418,6 +2418,195 @@ public fun CharArray.random(random: Random): Char {
    return get(random.nextInt(size))
 }

+/**
+ * Returns a random element from this array, or `null` if this array is empty.
+ */
+@SinceKotlin("1.3")
+@ExperimentalStdlibApi
+@kotlin.internal.InlineOnly
+public inline fun <T> Array<out T>.randomOrNull(): T? {
+    return randomOrNull(Random)
+}
+
+/**
+ * Returns a random element from this array, or `null` if this array is empty.
+ */
+@SinceKotlin("1.3")
+@ExperimentalStdlibApi
+@kotlin.internal.InlineOnly
+public inline fun ByteArray.randomOrNull(): Byte? {
+    return randomOrNull(Random)
+}
+
+/**
+ * Returns a random element from this array, or `null` if this array is empty.
+ */
+@SinceKotlin("1.3")
+@ExperimentalStdlibApi
+@kotlin.internal.InlineOnly
+public inline fun ShortArray.randomOrNull(): Short? {
+    return randomOrNull(Random)
+}
+
+/**
+ * Returns a random element from this array, or `null` if this array is empty.
+ */
+@SinceKotlin("1.3")
+@ExperimentalStdlibApi
+@kotlin.internal.InlineOnly
+public inline fun IntArray.randomOrNull(): Int? {
+    return randomOrNull(Random)
+}
+
+/**
+ * Returns a random element from this array, or `null` if this array is empty.
+ */
+@SinceKotlin("1.3")
+@ExperimentalStdlibApi
+@kotlin.internal.InlineOnly
+public inline fun LongArray.randomOrNull(): Long? {
+    return randomOrNull(Random)
+}
+
+/**
+ * Returns a random element from this array, or `null` if this array is empty.
+ */
+@SinceKotlin("1.3")
+@ExperimentalStdlibApi
+@kotlin.internal.InlineOnly
+public inline fun FloatArray.randomOrNull(): Float? {
+    return randomOrNull(Random)
+}
+
+/**
+ * Returns a random element from this array, or `null` if this array is empty.
+ */
+@SinceKotlin("1.3")
+@ExperimentalStdlibApi
+@kotlin.internal.InlineOnly
+public inline fun DoubleArray.randomOrNull(): Double? {
+    return randomOrNull(Random)
+}
+
+/**
+ * Returns a random element from this array, or `null` if this array is empty.
+ */
+@SinceKotlin("1.3")
+@ExperimentalStdlibApi
+@kotlin.internal.InlineOnly
+public inline fun BooleanArray.randomOrNull(): Boolean? {
+    return randomOrNull(Random)
+}
+
+/**
+ * Returns a random element from this array, or `null` if this array is empty.
+ */
+@SinceKotlin("1.3")
+@ExperimentalStdlibApi
+@kotlin.internal.InlineOnly
+public inline fun CharArray.randomOrNull(): Char? {
+    return randomOrNull(Random)
+}
+
+/**
+ * Returns a random element from this array using the specified source of randomness, or `null` if this array is empty.
+ */
+@SinceKotlin("1.3")
+@ExperimentalStdlibApi
+public fun <T> Array<out T>.randomOrNull(random: Random): T? {
+    if (isEmpty())
+        return null
+    return get(random.nextInt(size))
+}
+
+/**
+ * Returns a random element from this array using the specified source of randomness, or `null` if this array is empty.
+ */
+@SinceKotlin("1.3")
+@ExperimentalStdlibApi
+public fun ByteArray.randomOrNull(random: Random): Byte? {
+    if (isEmpty())
+        return null
+    return get(random.nextInt(size))
+}
+
+/**
+ * Returns a random element from this array using the specified source of randomness, or `null` if this array is empty.
+ */
+@SinceKotlin("1.3")
+@ExperimentalStdlibApi
+public fun ShortArray.randomOrNull(random: Random): Short? {
+    if (isEmpty())
+        return null
+    return get(random.nextInt(size))
+}
+
+/**
+ * Returns a random element from this array using the specified source of randomness, or `null` if this array is empty.
+ */
+@SinceKotlin("1.3")
+@ExperimentalStdlibApi
+public fun IntArray.randomOrNull(random: Random): Int? {
+    if (isEmpty())
+        return null
+    return get(random.nextInt(size))
+}
+
+/**
+ * Returns a random element from this array using the specified source of randomness, or `null` if this array is empty.
+ */
+@SinceKotlin("1.3")
+@ExperimentalStdlibApi
+public fun LongArray.randomOrNull(random: Random): Long? {
+    if (isEmpty())
+        return null
+    return get(random.nextInt(size))
+}
+
+/**
+ * Returns a random element from this array using the specified source of randomness, or `null` if this array is empty.
+ */
+@SinceKotlin("1.3")
+@ExperimentalStdlibApi
+public fun FloatArray.randomOrNull(random: Random): Float? {
+    if (isEmpty())
+        return null
+    return get(random.nextInt(size))
+}
+
+/**
+ * Returns a random element from this array using the specified source of randomness, or `null` if this array is empty.
+ */
+@SinceKotlin("1.3")
+@ExperimentalStdlibApi
+public fun DoubleArray.randomOrNull(random: Random): Double? {
+    if (isEmpty())
+        return null
+    return get(random.nextInt(size))
+}
+
+/**
+ * Returns a random element from this array using the specified source of randomness, or `null` if this array is empty.
+ */
+@SinceKotlin("1.3")
+@ExperimentalStdlibApi
+public fun BooleanArray.randomOrNull(random: Random): Boolean? {
+    if (isEmpty())
+        return null
+    return get(random.nextInt(size))
+}
+
+/**
+ * Returns a random element from this array using the specified source of randomness, or `null` if this array is empty.
+ */
+@SinceKotlin("1.3")
+@ExperimentalStdlibApi
+public fun CharArray.randomOrNull(random: Random): Char? {
+    if (isEmpty())
+        return null
+    return get(random.nextInt(size))
+}
+
 /**
 * Returns the single element, or throws an exception if the array is empty or has more than one element.
 */