Scala example source code file (BigDecimal.scala)

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Java - Scala tags/keywords

bigdecimal, bigdecimalinstances, bigdecimalmultiplicationnewtype, enum, int, monoid, multiplication, none, show

The BigDecimal.scala Scala example source code

package scalaz
package std
package math

trait BigDecimalInstances {
  implicit val bigDecimalInstance: Monoid[BigDecimal] with Enum[BigDecimal] with Show[BigDecimal] = new Monoid[BigDecimal] with Enum[BigDecimal] with Show[BigDecimal] {
    override def shows(f: BigDecimal) = f.toString

    def append(f1: BigDecimal, f2: => BigDecimal) = f1 + f2

    def zero = 0L

    def order(x: BigDecimal, y: BigDecimal) = if (x < y) Ordering.LT else if (x == y) Ordering.EQ else Ordering.GT

    def succ(b: BigDecimal) = b + 1
    def pred(b: BigDecimal) = b - 1
    override def succn(a: Int, b: BigDecimal) = b + a
    override def predn(a: Int, b: BigDecimal) = b - a
    override def min = None
    override def max = None
  }

  import Tags.Multiplication

  implicit val BigDecimalMultiplicationNewType: Monoid[BigDecimal @@ Multiplication] = new Monoid[BigDecimal @@ Multiplication] {
    def append(f1: BigDecimal @@ Multiplication, f2: => BigDecimal @@ Multiplication) = Multiplication(Tag.unwrap(f1) * Tag.unwrap(f2))

    def zero = Multiplication(1)
  }
}

object bigDecimal extends BigDecimalInstances