diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/library/scala/math/BigDecimal.scala | 15 | ||||
| -rw-r--r-- | src/library/scala/math/BigInt.scala | 38 |
2 files changed, 52 insertions, 1 deletions
diff --git a/src/library/scala/math/BigDecimal.scala b/src/library/scala/math/BigDecimal.scala index c1f45eccfb..cb42b76b51 100644 --- a/src/library/scala/math/BigDecimal.scala +++ b/src/library/scala/math/BigDecimal.scala @@ -183,7 +183,8 @@ extends ScalaNumber with ScalaNumericConversions with Serializable { override def equals (that: Any): Boolean = that match { case that: BigDecimal => this equals that case that: BigInt => this.toBigIntExact exists (that equals _) - case _: Float | _: Double => unifiedPrimitiveEquals(that) + case that: Double => isValidDouble && toDouble == that + case that: Float => isValidFloat && toFloat == that case _ => isValidLong && unifiedPrimitiveEquals(that) } override def isValidByte = noArithmeticException(toByteExact) @@ -191,6 +192,18 @@ extends ScalaNumber with ScalaNumericConversions with Serializable { override def isValidChar = isValidInt && toIntExact >= Char.MinValue && toIntExact <= Char.MaxValue override def isValidInt = noArithmeticException(toIntExact) def isValidLong = noArithmeticException(toLongExact) + /** Returns `true` iff this can be represented exactly by [[scala.Float]]; otherwise returns `false`. + */ + def isValidFloat = { + val f = toFloat + !f.isInfinity && bigDecimal.compareTo(new java.math.BigDecimal(f)) == 0 + } + /** Returns `true` iff this can be represented exactly by [[scala.Double]]; otherwise returns `false`. + */ + def isValidDouble = { + val d = toDouble + !d.isInfinity && bigDecimal.compareTo(new java.math.BigDecimal(d)) == 0 + } private def noArithmeticException(body: => Unit): Boolean = { try { body ; true } diff --git a/src/library/scala/math/BigInt.scala b/src/library/scala/math/BigInt.scala index 8a53afaa62..dbec30b2fe 100644 --- a/src/library/scala/math/BigInt.scala +++ b/src/library/scala/math/BigInt.scala @@ -20,6 +20,7 @@ object BigInt { private val minCached = -1024 private val maxCached = 1024 private val cache = new Array[BigInt](maxCached - minCached + 1) + private val minusOne = BigInteger.valueOf(-1) @deprecated("Use Long.MinValue", "2.9.0") val MinLong = BigInt(Long.MinValue) @@ -122,6 +123,8 @@ class BigInt(val bigInteger: BigInteger) extends ScalaNumber with ScalaNumericCo override def equals(that: Any): Boolean = that match { case that: BigInt => this equals that case that: BigDecimal => that.toBigIntExact exists (this equals _) + case that: Double => isValidDouble && toDouble == that + case that: Float => isValidFloat && toFloat == that case x => isValidLong && unifiedPrimitiveEquals(x) } override def isValidByte = this >= Byte.MinValue && this <= Byte.MaxValue @@ -129,6 +132,41 @@ class BigInt(val bigInteger: BigInteger) extends ScalaNumber with ScalaNumericCo override def isValidChar = this >= Char.MinValue && this <= Char.MaxValue override def isValidInt = this >= Int.MinValue && this <= Int.MaxValue def isValidLong = this >= Long.MinValue && this <= Long.MaxValue + /** Returns `true` iff this can be represented exactly by [[scala.Float]]; otherwise returns `false`. + */ + def isValidFloat = { + val bitLen = bitLength + (bitLen <= 24 || + { + val lowest = lowestSetBit + bitLen <= java.lang.Float.MAX_EXPONENT + 1 && // exclude this < -2^128 && this >= 2^128 + lowest >= bitLen - 24 && + lowest < java.lang.Float.MAX_EXPONENT + 1 // exclude this == -2^128 + } + ) && !bitLengthOverflow + } + /** Returns `true` iff this can be represented exactly by [[scala.Double]]; otherwise returns `false`. + */ + def isValidDouble = { + val bitLen = bitLength + (bitLen <= 53 || + { + val lowest = lowestSetBit + bitLen <= java.lang.Double.MAX_EXPONENT + 1 && // exclude this < -2^1024 && this >= 2^1024 + lowest >= bitLen - 53 && + lowest < java.lang.Double.MAX_EXPONENT + 1 // exclude this == -2^1024 + } + ) && !bitLengthOverflow + } + /** Some implementations of java.math.BigInteger allow huge values with bit length greater than Int.MaxValue . + * The BigInteger.bitLength method returns truncated bit length in this case . + * This method tests if result of bitLength is valid. + * This method will become unnecessary if BigInt constructors reject huge BigIntegers. + */ + private def bitLengthOverflow = { + val shifted = bigInteger.shiftRight(Int.MaxValue) + (shifted.signum != 0) && !(shifted equals BigInt.minusOne) + } protected[math] def isWhole = true def underlying = bigInteger |