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Diffstat (limited to 'examples/scala-js/scalalib/overrides-2.11/scala/collection/immutable/NumericRange.scala')
-rw-r--r-- | examples/scala-js/scalalib/overrides-2.11/scala/collection/immutable/NumericRange.scala | 346 |
1 files changed, 0 insertions, 346 deletions
diff --git a/examples/scala-js/scalalib/overrides-2.11/scala/collection/immutable/NumericRange.scala b/examples/scala-js/scalalib/overrides-2.11/scala/collection/immutable/NumericRange.scala deleted file mode 100644 index 51f9f68..0000000 --- a/examples/scala-js/scalalib/overrides-2.11/scala/collection/immutable/NumericRange.scala +++ /dev/null @@ -1,346 +0,0 @@ -/* __ *\ -** ________ ___ / / ___ Scala API ** -** / __/ __// _ | / / / _ | (c) 2006-2013, LAMP/EPFL ** -** __\ \/ /__/ __ |/ /__/ __ | http://scala-lang.org/ ** -** /____/\___/_/ |_/____/_/ | | ** -** |/ ** -\* */ - -package scala -package collection -package immutable - -import mutable.{ Builder, ListBuffer } - -/** `NumericRange` is a more generic version of the - * `Range` class which works with arbitrary types. - * It must be supplied with an `Integral` implementation of the - * range type. - * - * Factories for likely types include `Range.BigInt`, `Range.Long`, - * and `Range.BigDecimal`. `Range.Int` exists for completeness, but - * the `Int`-based `scala.Range` should be more performant. - * - * {{{ - * val r1 = new Range(0, 100, 1) - * val veryBig = Int.MaxValue.toLong + 1 - * val r2 = Range.Long(veryBig, veryBig + 100, 1) - * assert(r1 sameElements r2.map(_ - veryBig)) - * }}} - * - * TODO: Now the specialization exists there is no clear reason to have - * separate classes for Range/NumericRange. Investigate and consolidate. - * - * @author Paul Phillips - * @version 2.8 - * @define Coll `NumericRange` - * @define coll numeric range - * @define mayNotTerminateInf - * @define willNotTerminateInf - */ -abstract class NumericRange[T] - (val start: T, val end: T, val step: T, val isInclusive: Boolean) - (implicit num: Integral[T]) -extends AbstractSeq[T] with IndexedSeq[T] with Serializable { - /** Note that NumericRange must be invariant so that constructs - * such as "1L to 10 by 5" do not infer the range type as AnyVal. - */ - import num._ - - // See comment in Range for why this must be lazy. - private lazy val numRangeElements: Int = - NumericRange.count(start, end, step, isInclusive) - - override def length = numRangeElements - override def isEmpty = length == 0 - override lazy val last: T = - if (length == 0) Nil.last - else locationAfterN(length - 1) - - /** Create a new range with the start and end values of this range and - * a new `step`. - */ - def by(newStep: T): NumericRange[T] = copy(start, end, newStep) - - /** Create a copy of this range. - */ - def copy(start: T, end: T, step: T): NumericRange[T] - - override def foreach[U](f: T => U) { - var count = 0 - var current = start - while (count < length) { - f(current) - current += step - count += 1 - } - } - - // TODO: these private methods are straight copies from Range, duplicated - // to guard against any (most likely illusory) performance drop. They should - // be eliminated one way or another. - - // Tests whether a number is within the endpoints, without testing - // whether it is a member of the sequence (i.e. when step > 1.) - private def isWithinBoundaries(elem: T) = !isEmpty && ( - (step > zero && start <= elem && elem <= last ) || - (step < zero && last <= elem && elem <= start) - ) - // Methods like apply throw exceptions on invalid n, but methods like take/drop - // are forgiving: therefore the checks are with the methods. - private def locationAfterN(n: Int): T = start + (step * fromInt(n)) - - // When one drops everything. Can't ever have unchecked operations - // like "end + 1" or "end - 1" because ranges involving Int.{ MinValue, MaxValue } - // will overflow. This creates an exclusive range where start == end - // based on the given value. - private def newEmptyRange(value: T) = NumericRange(value, value, step) - - final override def take(n: Int): NumericRange[T] = ( - if (n <= 0 || length == 0) newEmptyRange(start) - else if (n >= length) this - else new NumericRange.Inclusive(start, locationAfterN(n - 1), step) - ) - - final override def drop(n: Int): NumericRange[T] = ( - if (n <= 0 || length == 0) this - else if (n >= length) newEmptyRange(end) - else copy(locationAfterN(n), end, step) - ) - - def apply(idx: Int): T = { - if (idx < 0 || idx >= length) throw new IndexOutOfBoundsException(idx.toString) - else locationAfterN(idx) - } - - import NumericRange.defaultOrdering - - override def min[T1 >: T](implicit ord: Ordering[T1]): T = - if (ord eq defaultOrdering(num)) { - if (num.signum(step) > 0) start - else last - } else super.min(ord) - - override def max[T1 >: T](implicit ord: Ordering[T1]): T = - if (ord eq defaultOrdering(num)) { - if (num.signum(step) > 0) last - else start - } else super.max(ord) - - // Motivated by the desire for Double ranges with BigDecimal precision, - // we need some way to map a Range and get another Range. This can't be - // done in any fully general way because Ranges are not arbitrary - // sequences but step-valued, so we have a custom method only we can call - // which we promise to use responsibly. - // - // The point of it all is that - // - // 0.0 to 1.0 by 0.1 - // - // should result in - // - // NumericRange[Double](0.0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0) - // - // and not - // - // NumericRange[Double](0.0, 0.1, 0.2, 0.30000000000000004, 0.4, 0.5, 0.6000000000000001, 0.7000000000000001, 0.8, 0.9) - // - // or perhaps more importantly, - // - // (0.1 to 0.3 by 0.1 contains 0.3) == true - // - private[immutable] def mapRange[A](fm: T => A)(implicit unum: Integral[A]): NumericRange[A] = { - val self = this - - // XXX This may be incomplete. - new NumericRange[A](fm(start), fm(end), fm(step), isInclusive) { - def copy(start: A, end: A, step: A): NumericRange[A] = - if (isInclusive) NumericRange.inclusive(start, end, step) - else NumericRange(start, end, step) - - private lazy val underlyingRange: NumericRange[T] = self - override def foreach[U](f: A => U) { underlyingRange foreach (x => f(fm(x))) } - override def isEmpty = underlyingRange.isEmpty - override def apply(idx: Int): A = fm(underlyingRange(idx)) - override def containsTyped(el: A) = underlyingRange exists (x => fm(x) == el) - } - } - - // a well-typed contains method. - def containsTyped(x: T): Boolean = - isWithinBoundaries(x) && (((x - start) % step) == zero) - - override def contains[A1 >: T](x: A1): Boolean = - try containsTyped(x.asInstanceOf[T]) - catch { case _: ClassCastException => false } - - final override def sum[B >: T](implicit num: Numeric[B]): B = { - // arithmetic series formula can be used for regular addition - if ((num eq scala.math.Numeric.IntIsIntegral)|| - (num eq scala.math.Numeric.ShortIsIntegral)|| - (num eq scala.math.Numeric.ByteIsIntegral)|| - (num eq scala.math.Numeric.CharIsIntegral)|| - (num eq scala.math.Numeric.LongIsIntegral)) { - val numAsIntegral = num.asInstanceOf[Integral[B]] - import numAsIntegral._ - if (isEmpty) num fromInt 0 - else if (numRangeElements == 1) head - else ((num fromInt numRangeElements) * (head + last) / (num fromInt 2)) - } else { - // user provided custom Numeric, we cannot rely on arithmetic series formula - if (isEmpty) num.zero - else { - var acc = num.zero - var i = head - var idx = 0 - while(idx < length) { - acc = num.plus(acc, i) - i = i + step - idx = idx + 1 - } - acc - } - } - } - - override lazy val hashCode = super.hashCode() - override def equals(other: Any) = other match { - case x: NumericRange[_] => - (x canEqual this) && (length == x.length) && ( - (length == 0) || // all empty sequences are equal - (start == x.start && last == x.last) // same length and same endpoints implies equality - ) - case _ => - super.equals(other) - } - - override def toString() = { - val endStr = if (length > Range.MAX_PRINT) ", ... )" else ")" - take(Range.MAX_PRINT).mkString("NumericRange(", ", ", endStr) - } -} - -/** A companion object for numeric ranges. - */ -object NumericRange { - - /** Calculates the number of elements in a range given start, end, step, and - * whether or not it is inclusive. Throws an exception if step == 0 or - * the number of elements exceeds the maximum Int. - */ - def count[T](start: T, end: T, step: T, isInclusive: Boolean)(implicit num: Integral[T]): Int = { - val zero = num.zero - val upward = num.lt(start, end) - val posStep = num.gt(step, zero) - - if (step == zero) throw new IllegalArgumentException("step cannot be 0.") - else if (start == end) if (isInclusive) 1 else 0 - else if (upward != posStep) 0 - else { - /* We have to be frightfully paranoid about running out of range. - * We also can't assume that the numbers will fit in a Long. - * We will assume that if a > 0, -a can be represented, and if - * a < 0, -a+1 can be represented. We also assume that if we - * can't fit in Int, we can represent 2*Int.MaxValue+3 (at least). - * And we assume that numbers wrap rather than cap when they overflow. - */ - // Check whether we can short-circuit by deferring to Int range. - val startint = num.toInt(start) - if (start == num.fromInt(startint)) { - val endint = num.toInt(end) - if (end == num.fromInt(endint)) { - val stepint = num.toInt(step) - if (step == num.fromInt(stepint)) { - return { - if (isInclusive) Range.inclusive(startint, endint, stepint).length - else Range (startint, endint, stepint).length - } - } - } - } - // If we reach this point, deferring to Int failed. - // Numbers may be big. - val one = num.one - val limit = num.fromInt(Int.MaxValue) - def check(t: T): T = - if (num.gt(t, limit)) throw new IllegalArgumentException("More than Int.MaxValue elements.") - else t - // If the range crosses zero, it might overflow when subtracted - val startside = num.signum(start) - val endside = num.signum(end) - num.toInt{ - if (startside*endside >= 0) { - // We're sure we can subtract these numbers. - // Note that we do not use .rem because of different conventions for Long and BigInt - val diff = num.minus(end, start) - val quotient = check(num.quot(diff, step)) - val remainder = num.minus(diff, num.times(quotient, step)) - if (!isInclusive && zero == remainder) quotient else check(num.plus(quotient, one)) - } - else { - // We might not even be able to subtract these numbers. - // Jump in three pieces: - // * start to -1 or 1, whichever is closer (waypointA) - // * one step, which will take us at least to 0 (ends at waypointB) - // * there to the end - val negone = num.fromInt(-1) - val startlim = if (posStep) negone else one - val startdiff = num.minus(startlim, start) - val startq = check(num.quot(startdiff, step)) - val waypointA = if (startq == zero) start else num.plus(start, num.times(startq, step)) - val waypointB = num.plus(waypointA, step) - check { - if (num.lt(waypointB, end) != upward) { - // No last piece - if (isInclusive && waypointB == end) num.plus(startq, num.fromInt(2)) - else num.plus(startq, one) - } - else { - // There is a last piece - val enddiff = num.minus(end,waypointB) - val endq = check(num.quot(enddiff, step)) - val last = if (endq == zero) waypointB else num.plus(waypointB, num.times(endq, step)) - // Now we have to tally up all the pieces - // 1 for the initial value - // startq steps to waypointA - // 1 step to waypointB - // endq steps to the end (one less if !isInclusive and last==end) - num.plus(startq, num.plus(endq, if (!isInclusive && last==end) one else num.fromInt(2))) - } - } - } - } - } - } - - class Inclusive[T](start: T, end: T, step: T)(implicit num: Integral[T]) - extends NumericRange(start, end, step, true) { - def copy(start: T, end: T, step: T): Inclusive[T] = - NumericRange.inclusive(start, end, step) - - def exclusive: Exclusive[T] = NumericRange(start, end, step) - } - - class Exclusive[T](start: T, end: T, step: T)(implicit num: Integral[T]) - extends NumericRange(start, end, step, false) { - def copy(start: T, end: T, step: T): Exclusive[T] = - NumericRange(start, end, step) - - def inclusive: Inclusive[T] = NumericRange.inclusive(start, end, step) - } - - def apply[T](start: T, end: T, step: T)(implicit num: Integral[T]): Exclusive[T] = - new Exclusive(start, end, step) - def inclusive[T](start: T, end: T, step: T)(implicit num: Integral[T]): Inclusive[T] = - new Inclusive(start, end, step) - - private[collection] val defaultOrdering = Map[Numeric[_], Ordering[_]]( - Numeric.IntIsIntegral -> Ordering.Int, - Numeric.ShortIsIntegral -> Ordering.Short, - Numeric.ByteIsIntegral -> Ordering.Byte, - Numeric.CharIsIntegral -> Ordering.Char, - Numeric.LongIsIntegral -> Ordering.Long - ) - -} - |