sapphire-lang 0.7.0

# Set is an unordered collection of unique values.
# Backed natively by an insertion-ordered Vec with linear deduplication.
# Construction: Set.new or Set.new([1, 2, 3])
#
class Set {
  # Returns a new List built by calling the block once per element.
  #
  #   Set.new([1, 2, 3]).map { |x| x * 2 }   # [2, 4, 6]
  #
  def map {
    result = []
    each { |x| result.append(yield(x)) }
    result
  }

  # Returns a new Set containing only elements for which the block returns true.
  #
  #   Set.new([1, 2, 3, 4]).select { |x| x > 2 }   # Set{3, 4}
  #
  def select {
    result = Set.new
    each { |x| result.add(x) if yield(x) }
    result
  }

  # Returns a new Set containing elements for which the block returns false.
  #
  #   Set.new([1, 2, 3]).reject { |x| x == 2 }   # Set{1, 3}
  #
  def reject {
    result = Set.new
    each { |x| result.add(x) if !yield(x) }
    result
  }

  # Returns true if the block returns truthy for at least one element.
  #
  #   Set.new([1, 2, 3]).any? { |x| x > 2 }   # true
  #
  def any?() {
    each { |x| return true if yield(x) }
    false
  }

  # Returns true if the block returns truthy for every element. Empty sets are true.
  #
  #   Set.new([1, 2, 3]).all? { |x| x > 0 }   # true
  #
  def all?() {
    each { |x| return false if !yield(x) }
    true
  }

  # Returns true if the block never returns truthy. Empty sets are true.
  #
  #   Set.new([1, 2, 3]).none? { |x| x > 9 }   # true
  #
  def none?() {
    each { |x| return false if yield(x) }
    true
  }

  # Yields each element with its zero-based insertion index.
  #
  #   Set.new(["a", "b"]).each_with_index { |item, i| print "#{i}: #{item}" }
  #
  def each_with_index {
    i = 0
    each { |x|
      yield(x, i)
      i = i + 1
    }
  }
}