Commonize Float.rangeTo(Float) #KT-35299

2019-12-06 08:23:04 +03:00
parent b76c984b26
commit 19e001afad
3 changed files with 69 additions and 88 deletions
@@ -8,24 +8,6 @@

 package kotlin.ranges

-/**
- * Represents a range of floating point numbers.
- * Extends [ClosedRange] interface providing custom operation [lessThanOrEquals] for comparing values of range domain type.
- *
- * This interface is implemented by floating point ranges returned by [Float.rangeTo] and [Double.rangeTo] operators to
- * achieve IEEE-754 comparison order instead of total order of floating point numbers.
- */
-@SinceKotlin("1.1")
-public interface ClosedFloatingPointRange<T : Comparable<T>> : ClosedRange<T> {
-    override fun contains(value: T): Boolean = lessThanOrEquals(start, value) && lessThanOrEquals(value, endInclusive)
-    override fun isEmpty(): Boolean = !lessThanOrEquals(start, endInclusive)
-
-    /**
-     * Compares two values of range domain type and returns true if first is less than or equal to second.
-     */
-    fun lessThanOrEquals(a: T, b: T): Boolean
-}
-
 /**
 * Represents a range of [Comparable] values.
 */
@@ -46,6 +28,34 @@ private open class ComparableRange<T : Comparable<T>>(
    override fun toString(): String = "$start..$endInclusive"
 }

+/**
+ * Creates a range from this [Comparable] value to the specified [that] value.
+ *
+ * This value needs to be smaller than [that] value, otherwise the returned range will be empty.
+ * @sample samples.ranges.Ranges.rangeFromComparable
+ */
+public operator fun <T : Comparable<T>> T.rangeTo(that: T): ClosedRange<T> = ComparableRange(this, that)
+
+
+/**
+ * Represents a range of floating point numbers.
+ * Extends [ClosedRange] interface providing custom operation [lessThanOrEquals] for comparing values of range domain type.
+ *
+ * This interface is implemented by floating point ranges returned by [Float.rangeTo] and [Double.rangeTo] operators to
+ * achieve IEEE-754 comparison order instead of total order of floating point numbers.
+ */
+@SinceKotlin("1.1")
+public interface ClosedFloatingPointRange<T : Comparable<T>> : ClosedRange<T> {
+    override fun contains(value: T): Boolean = lessThanOrEquals(start, value) && lessThanOrEquals(value, endInclusive)
+    override fun isEmpty(): Boolean = !lessThanOrEquals(start, endInclusive)
+
+    /**
+     * Compares two values of range domain type and returns true if first is less than or equal to second.
+     */
+    fun lessThanOrEquals(a: T, b: T): Boolean
+}
+
+
 /**
 * A closed range of values of type `Double`.
 *
@@ -77,15 +87,6 @@ private class ClosedDoubleRange(
    override fun toString(): String = "$_start..$_endInclusive"
 }

-
-/**
- * Creates a range from this [Comparable] value to the specified [that] value.
- *
- * This value needs to be smaller than [that] value, otherwise the returned range will be empty.
- * @sample samples.ranges.Ranges.rangeFromComparable
- */
-public operator fun <T : Comparable<T>> T.rangeTo(that: T): ClosedRange<T> = ComparableRange(this, that)
-
 /**
 * Creates a range from this [Double] value to the specified [that] value.
 *
@@ -96,6 +97,47 @@ public operator fun <T : Comparable<T>> T.rangeTo(that: T): ClosedRange<T> = Com
 public operator fun Double.rangeTo(that: Double): ClosedFloatingPointRange<Double> = ClosedDoubleRange(this, that)


+/**
+ * A closed range of values of type `Float`.
+ *
+ * Numbers are compared with the ends of this range according to IEEE-754.
+ */
+private class ClosedFloatRange(
+    start: Float,
+    endInclusive: Float
+) : ClosedFloatingPointRange<Float> {
+    private val _start = start
+    private val _endInclusive = endInclusive
+    override val start: Float get() = _start
+    override val endInclusive: Float get() = _endInclusive
+
+    override fun lessThanOrEquals(a: Float, b: Float): Boolean = a <= b
+
+    override fun contains(value: Float): Boolean = value >= _start && value <= _endInclusive
+    override fun isEmpty(): Boolean = !(_start <= _endInclusive)
+
+    override fun equals(other: Any?): Boolean {
+        return other is ClosedFloatRange && (isEmpty() && other.isEmpty() ||
+                _start == other._start && _endInclusive == other._endInclusive)
+    }
+
+    override fun hashCode(): Int {
+        return if (isEmpty()) -1 else 31 * _start.hashCode() + _endInclusive.hashCode()
+    }
+
+    override fun toString(): String = "$_start..$_endInclusive"
+}
+
+/**
+ * Creates a range from this [Float] value to the specified [that] value.
+ *
+ * Numbers are compared with the ends of this range according to IEEE-754.
+ * @sample samples.ranges.Ranges.rangeFromFloat
+ */
+@SinceKotlin("1.1")
+public operator fun Float.rangeTo(that: Float): ClosedFloatingPointRange<Float> = ClosedFloatRange(this, that)
+
+
 /**
 * Returns `true` if this iterable range contains the specified [element].
 *