Class: PGN::Move

Inherits:
Object
  • Object
show all
Defined in:
lib/pgn/move.rb

Overview

Move knows how to parse a move string in standard algebraic notation to extract all relevant information.

See Also:

Constant Summary collapse

SAN_REGEX =

A regular expression for matching moves in standard algebraic notation

/
  (?<piece>          [BKNQR]      ){0}
  (?<destination>    [a-h][1-8]   ){0}
  (?<promotion>      =[BNQR]      ){0}
  (?<check>          [#+]         ){0}
  (?<capture>        x            ){0}
  (?<disambiguation> [a-h]?[1-8]? ){0}

  (?<castle>         O-O(-O)?     ){0}

  (?<normal>
    \g<piece>?
    \g<disambiguation>
    \g<capture>?
    \g<destination>
    \g<promotion>?
  ){0}

  \A (\g<castle> | \g<normal>) \g<check>? \z
/x.freeze

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(move, player) ⇒ Move

Returns a new instance of Move.

Examples:

PGN::Move.new("e4", :white)

Parameters:

  • move (String) —

    the move in SAN

  • player (Symbol) —

    the player making the move



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# File 'lib/pgn/move.rb', line 91

def initialize(move, player)
  self.player = player
  self.san    = move

  match = move.match(SAN_REGEX)
  return  if match.nil?

  match.names.each do |name|
    send("#{name}=", match[name]) if respond_to?(name)
  end
end

Instance Attribute Details

#capture ⇒ String?

Returns whether the move is a capture.

Examples:

move.capture #=> "x"

Returns:

  • (String, nil) —

    whether the move is a capture



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# File 'lib/pgn/move.rb', line 59

class Move
  attr_accessor :san, :player
  attr_accessor :piece, :destination, :promotion, :check, :capture, :disambiguation, :castle
  # A regular expression for matching moves in standard algebraic
  # notation
  #
  SAN_REGEX = /
    (?<piece>          [BKNQR]      ){0}
    (?<destination>    [a-h][1-8]   ){0}
    (?<promotion>      =[BNQR]      ){0}
    (?<check>          [#+]         ){0}
    (?<capture>        x            ){0}
    (?<disambiguation> [a-h]?[1-8]? ){0}

    (?<castle>         O-O(-O)?     ){0}

    (?<normal>
      \g<piece>?
      \g<disambiguation>
      \g<capture>?
      \g<destination>
      \g<promotion>?
    ){0}

    \A (\g<castle> | \g<normal>) \g<check>? \z
  /x.freeze

  # @param move [String] the move in SAN
  # @param player [Symbol] the player making the move
  # @example
  #   PGN::Move.new("e4", :white)
  #
  def initialize(move, player)
    self.player = player
    self.san    = move

    match = move.match(SAN_REGEX)
    return  if match.nil?

    match.names.each do |name|
      send("#{name}=", match[name]) if respond_to?(name)
    end
  end

  def piece=(val)
    return if san.match('O-O')

    val ||= 'P'
    @piece = black? ? val.downcase : val
  end

  def promotion=(val)
    if val
      val.downcase! if black?
      @promotion = val.delete('=')
    end
  end

  def capture=(val)
    @capture = !!val
  end

  def disambiguation=(val)
    @disambiguation = (val == '' ? nil : val)
  end

  def castle=(val)
    if val
      @castle = 'K' if val == 'O-O'
      @castle = 'Q' if val == 'O-O-O'
      @castle.downcase! if black?
    end
  end

  # @return [Boolean] whether the move results in check
  #
  def check?
    check == '+'
  end

  # @return [Boolean] whether the move results in checkmate
  #
  def checkmate?
    check == '#'
  end

  # @return [Boolean] whether it's white's turn
  #
  def white?
    player == :white
  end

  # @return [Boolean] whether it's black's turn
  #
  def black?
    player == :black
  end

  # @return [Boolean] whether the piece being moved is a pawn
  #
  def pawn?
    %w[P p].include?(piece)
  end
end

#castle ⇒ String?

Returns the castle string if applicable.

Examples:

move1.castle #=> "O-O-O"
move2.castle #=> "O-O"

Returns:

  • (String, nil) —

    the castle string if applicable



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# File 'lib/pgn/move.rb', line 59

class Move
  attr_accessor :san, :player
  attr_accessor :piece, :destination, :promotion, :check, :capture, :disambiguation, :castle
  # A regular expression for matching moves in standard algebraic
  # notation
  #
  SAN_REGEX = /
    (?<piece>          [BKNQR]      ){0}
    (?<destination>    [a-h][1-8]   ){0}
    (?<promotion>      =[BNQR]      ){0}
    (?<check>          [#+]         ){0}
    (?<capture>        x            ){0}
    (?<disambiguation> [a-h]?[1-8]? ){0}

    (?<castle>         O-O(-O)?     ){0}

    (?<normal>
      \g<piece>?
      \g<disambiguation>
      \g<capture>?
      \g<destination>
      \g<promotion>?
    ){0}

    \A (\g<castle> | \g<normal>) \g<check>? \z
  /x.freeze

  # @param move [String] the move in SAN
  # @param player [Symbol] the player making the move
  # @example
  #   PGN::Move.new("e4", :white)
  #
  def initialize(move, player)
    self.player = player
    self.san    = move

    match = move.match(SAN_REGEX)
    return  if match.nil?

    match.names.each do |name|
      send("#{name}=", match[name]) if respond_to?(name)
    end
  end

  def piece=(val)
    return if san.match('O-O')

    val ||= 'P'
    @piece = black? ? val.downcase : val
  end

  def promotion=(val)
    if val
      val.downcase! if black?
      @promotion = val.delete('=')
    end
  end

  def capture=(val)
    @capture = !!val
  end

  def disambiguation=(val)
    @disambiguation = (val == '' ? nil : val)
  end

  def castle=(val)
    if val
      @castle = 'K' if val == 'O-O'
      @castle = 'Q' if val == 'O-O-O'
      @castle.downcase! if black?
    end
  end

  # @return [Boolean] whether the move results in check
  #
  def check?
    check == '+'
  end

  # @return [Boolean] whether the move results in checkmate
  #
  def checkmate?
    check == '#'
  end

  # @return [Boolean] whether it's white's turn
  #
  def white?
    player == :white
  end

  # @return [Boolean] whether it's black's turn
  #
  def black?
    player == :black
  end

  # @return [Boolean] whether the piece being moved is a pawn
  #
  def pawn?
    %w[P p].include?(piece)
  end
end

#check ⇒ String?

Returns whether the move results in check or mate.

Examples:

move1.check #=> "+"
move2.check #=> "#"

Returns:

  • (String, nil) —

    whether the move results in check or mate



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# File 'lib/pgn/move.rb', line 59

class Move
  attr_accessor :san, :player
  attr_accessor :piece, :destination, :promotion, :check, :capture, :disambiguation, :castle
  # A regular expression for matching moves in standard algebraic
  # notation
  #
  SAN_REGEX = /
    (?<piece>          [BKNQR]      ){0}
    (?<destination>    [a-h][1-8]   ){0}
    (?<promotion>      =[BNQR]      ){0}
    (?<check>          [#+]         ){0}
    (?<capture>        x            ){0}
    (?<disambiguation> [a-h]?[1-8]? ){0}

    (?<castle>         O-O(-O)?     ){0}

    (?<normal>
      \g<piece>?
      \g<disambiguation>
      \g<capture>?
      \g<destination>
      \g<promotion>?
    ){0}

    \A (\g<castle> | \g<normal>) \g<check>? \z
  /x.freeze

  # @param move [String] the move in SAN
  # @param player [Symbol] the player making the move
  # @example
  #   PGN::Move.new("e4", :white)
  #
  def initialize(move, player)
    self.player = player
    self.san    = move

    match = move.match(SAN_REGEX)
    return  if match.nil?

    match.names.each do |name|
      send("#{name}=", match[name]) if respond_to?(name)
    end
  end

  def piece=(val)
    return if san.match('O-O')

    val ||= 'P'
    @piece = black? ? val.downcase : val
  end

  def promotion=(val)
    if val
      val.downcase! if black?
      @promotion = val.delete('=')
    end
  end

  def capture=(val)
    @capture = !!val
  end

  def disambiguation=(val)
    @disambiguation = (val == '' ? nil : val)
  end

  def castle=(val)
    if val
      @castle = 'K' if val == 'O-O'
      @castle = 'Q' if val == 'O-O-O'
      @castle.downcase! if black?
    end
  end

  # @return [Boolean] whether the move results in check
  #
  def check?
    check == '+'
  end

  # @return [Boolean] whether the move results in checkmate
  #
  def checkmate?
    check == '#'
  end

  # @return [Boolean] whether it's white's turn
  #
  def white?
    player == :white
  end

  # @return [Boolean] whether it's black's turn
  #
  def black?
    player == :black
  end

  # @return [Boolean] whether the piece being moved is a pawn
  #
  def pawn?
    %w[P p].include?(piece)
  end
end

#destination ⇒ String?

Returns the destination square of the piece.

Examples:

move.destination #=> "e4"

Returns:

  • (String, nil) —

    the destination square of the piece



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# File 'lib/pgn/move.rb', line 59

class Move
  attr_accessor :san, :player
  attr_accessor :piece, :destination, :promotion, :check, :capture, :disambiguation, :castle
  # A regular expression for matching moves in standard algebraic
  # notation
  #
  SAN_REGEX = /
    (?<piece>          [BKNQR]      ){0}
    (?<destination>    [a-h][1-8]   ){0}
    (?<promotion>      =[BNQR]      ){0}
    (?<check>          [#+]         ){0}
    (?<capture>        x            ){0}
    (?<disambiguation> [a-h]?[1-8]? ){0}

    (?<castle>         O-O(-O)?     ){0}

    (?<normal>
      \g<piece>?
      \g<disambiguation>
      \g<capture>?
      \g<destination>
      \g<promotion>?
    ){0}

    \A (\g<castle> | \g<normal>) \g<check>? \z
  /x.freeze

  # @param move [String] the move in SAN
  # @param player [Symbol] the player making the move
  # @example
  #   PGN::Move.new("e4", :white)
  #
  def initialize(move, player)
    self.player = player
    self.san    = move

    match = move.match(SAN_REGEX)
    return  if match.nil?

    match.names.each do |name|
      send("#{name}=", match[name]) if respond_to?(name)
    end
  end

  def piece=(val)
    return if san.match('O-O')

    val ||= 'P'
    @piece = black? ? val.downcase : val
  end

  def promotion=(val)
    if val
      val.downcase! if black?
      @promotion = val.delete('=')
    end
  end

  def capture=(val)
    @capture = !!val
  end

  def disambiguation=(val)
    @disambiguation = (val == '' ? nil : val)
  end

  def castle=(val)
    if val
      @castle = 'K' if val == 'O-O'
      @castle = 'Q' if val == 'O-O-O'
      @castle.downcase! if black?
    end
  end

  # @return [Boolean] whether the move results in check
  #
  def check?
    check == '+'
  end

  # @return [Boolean] whether the move results in checkmate
  #
  def checkmate?
    check == '#'
  end

  # @return [Boolean] whether it's white's turn
  #
  def white?
    player == :white
  end

  # @return [Boolean] whether it's black's turn
  #
  def black?
    player == :black
  end

  # @return [Boolean] whether the piece being moved is a pawn
  #
  def pawn?
    %w[P p].include?(piece)
  end
end

#disambiguation ⇒ String?

Returns the disambiguation string if there is one.

Examples:

move.disambiguation #=> "3"

Returns:

  • (String, nil) —

    the disambiguation string if there is one



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# File 'lib/pgn/move.rb', line 59

class Move
  attr_accessor :san, :player
  attr_accessor :piece, :destination, :promotion, :check, :capture, :disambiguation, :castle
  # A regular expression for matching moves in standard algebraic
  # notation
  #
  SAN_REGEX = /
    (?<piece>          [BKNQR]      ){0}
    (?<destination>    [a-h][1-8]   ){0}
    (?<promotion>      =[BNQR]      ){0}
    (?<check>          [#+]         ){0}
    (?<capture>        x            ){0}
    (?<disambiguation> [a-h]?[1-8]? ){0}

    (?<castle>         O-O(-O)?     ){0}

    (?<normal>
      \g<piece>?
      \g<disambiguation>
      \g<capture>?
      \g<destination>
      \g<promotion>?
    ){0}

    \A (\g<castle> | \g<normal>) \g<check>? \z
  /x.freeze

  # @param move [String] the move in SAN
  # @param player [Symbol] the player making the move
  # @example
  #   PGN::Move.new("e4", :white)
  #
  def initialize(move, player)
    self.player = player
    self.san    = move

    match = move.match(SAN_REGEX)
    return  if match.nil?

    match.names.each do |name|
      send("#{name}=", match[name]) if respond_to?(name)
    end
  end

  def piece=(val)
    return if san.match('O-O')

    val ||= 'P'
    @piece = black? ? val.downcase : val
  end

  def promotion=(val)
    if val
      val.downcase! if black?
      @promotion = val.delete('=')
    end
  end

  def capture=(val)
    @capture = !!val
  end

  def disambiguation=(val)
    @disambiguation = (val == '' ? nil : val)
  end

  def castle=(val)
    if val
      @castle = 'K' if val == 'O-O'
      @castle = 'Q' if val == 'O-O-O'
      @castle.downcase! if black?
    end
  end

  # @return [Boolean] whether the move results in check
  #
  def check?
    check == '+'
  end

  # @return [Boolean] whether the move results in checkmate
  #
  def checkmate?
    check == '#'
  end

  # @return [Boolean] whether it's white's turn
  #
  def white?
    player == :white
  end

  # @return [Boolean] whether it's black's turn
  #
  def black?
    player == :black
  end

  # @return [Boolean] whether the piece being moved is a pawn
  #
  def pawn?
    %w[P p].include?(piece)
  end
end

#piece ⇒ String?

Note:

this is nil for castling

Note:

uppercase represents white, lowercase represents black

Returns the piece being moved.

Examples:

move1.piece #=> "Q"
move2.piece #=> "r"

Returns:

  • (String, nil) —

    the piece being moved



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# File 'lib/pgn/move.rb', line 59

class Move
  attr_accessor :san, :player
  attr_accessor :piece, :destination, :promotion, :check, :capture, :disambiguation, :castle
  # A regular expression for matching moves in standard algebraic
  # notation
  #
  SAN_REGEX = /
    (?<piece>          [BKNQR]      ){0}
    (?<destination>    [a-h][1-8]   ){0}
    (?<promotion>      =[BNQR]      ){0}
    (?<check>          [#+]         ){0}
    (?<capture>        x            ){0}
    (?<disambiguation> [a-h]?[1-8]? ){0}

    (?<castle>         O-O(-O)?     ){0}

    (?<normal>
      \g<piece>?
      \g<disambiguation>
      \g<capture>?
      \g<destination>
      \g<promotion>?
    ){0}

    \A (\g<castle> | \g<normal>) \g<check>? \z
  /x.freeze

  # @param move [String] the move in SAN
  # @param player [Symbol] the player making the move
  # @example
  #   PGN::Move.new("e4", :white)
  #
  def initialize(move, player)
    self.player = player
    self.san    = move

    match = move.match(SAN_REGEX)
    return  if match.nil?

    match.names.each do |name|
      send("#{name}=", match[name]) if respond_to?(name)
    end
  end

  def piece=(val)
    return if san.match('O-O')

    val ||= 'P'
    @piece = black? ? val.downcase : val
  end

  def promotion=(val)
    if val
      val.downcase! if black?
      @promotion = val.delete('=')
    end
  end

  def capture=(val)
    @capture = !!val
  end

  def disambiguation=(val)
    @disambiguation = (val == '' ? nil : val)
  end

  def castle=(val)
    if val
      @castle = 'K' if val == 'O-O'
      @castle = 'Q' if val == 'O-O-O'
      @castle.downcase! if black?
    end
  end

  # @return [Boolean] whether the move results in check
  #
  def check?
    check == '+'
  end

  # @return [Boolean] whether the move results in checkmate
  #
  def checkmate?
    check == '#'
  end

  # @return [Boolean] whether it's white's turn
  #
  def white?
    player == :white
  end

  # @return [Boolean] whether it's black's turn
  #
  def black?
    player == :black
  end

  # @return [Boolean] whether the piece being moved is a pawn
  #
  def pawn?
    %w[P p].include?(piece)
  end
end

#player ⇒ Symbol

Returns the current player.

Examples:

move.player #=> :white

Returns:

  • (Symbol) —

    the current player



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# File 'lib/pgn/move.rb', line 59

class Move
  attr_accessor :san, :player
  attr_accessor :piece, :destination, :promotion, :check, :capture, :disambiguation, :castle
  # A regular expression for matching moves in standard algebraic
  # notation
  #
  SAN_REGEX = /
    (?<piece>          [BKNQR]      ){0}
    (?<destination>    [a-h][1-8]   ){0}
    (?<promotion>      =[BNQR]      ){0}
    (?<check>          [#+]         ){0}
    (?<capture>        x            ){0}
    (?<disambiguation> [a-h]?[1-8]? ){0}

    (?<castle>         O-O(-O)?     ){0}

    (?<normal>
      \g<piece>?
      \g<disambiguation>
      \g<capture>?
      \g<destination>
      \g<promotion>?
    ){0}

    \A (\g<castle> | \g<normal>) \g<check>? \z
  /x.freeze

  # @param move [String] the move in SAN
  # @param player [Symbol] the player making the move
  # @example
  #   PGN::Move.new("e4", :white)
  #
  def initialize(move, player)
    self.player = player
    self.san    = move

    match = move.match(SAN_REGEX)
    return  if match.nil?

    match.names.each do |name|
      send("#{name}=", match[name]) if respond_to?(name)
    end
  end

  def piece=(val)
    return if san.match('O-O')

    val ||= 'P'
    @piece = black? ? val.downcase : val
  end

  def promotion=(val)
    if val
      val.downcase! if black?
      @promotion = val.delete('=')
    end
  end

  def capture=(val)
    @capture = !!val
  end

  def disambiguation=(val)
    @disambiguation = (val == '' ? nil : val)
  end

  def castle=(val)
    if val
      @castle = 'K' if val == 'O-O'
      @castle = 'Q' if val == 'O-O-O'
      @castle.downcase! if black?
    end
  end

  # @return [Boolean] whether the move results in check
  #
  def check?
    check == '+'
  end

  # @return [Boolean] whether the move results in checkmate
  #
  def checkmate?
    check == '#'
  end

  # @return [Boolean] whether it's white's turn
  #
  def white?
    player == :white
  end

  # @return [Boolean] whether it's black's turn
  #
  def black?
    player == :black
  end

  # @return [Boolean] whether the piece being moved is a pawn
  #
  def pawn?
    %w[P p].include?(piece)
  end
end

#promotion ⇒ String?

Returns the promotion piece, if applicable.

Returns:

  • (String, nil) —

    the promotion piece, if applicable



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# File 'lib/pgn/move.rb', line 59

class Move
  attr_accessor :san, :player
  attr_accessor :piece, :destination, :promotion, :check, :capture, :disambiguation, :castle
  # A regular expression for matching moves in standard algebraic
  # notation
  #
  SAN_REGEX = /
    (?<piece>          [BKNQR]      ){0}
    (?<destination>    [a-h][1-8]   ){0}
    (?<promotion>      =[BNQR]      ){0}
    (?<check>          [#+]         ){0}
    (?<capture>        x            ){0}
    (?<disambiguation> [a-h]?[1-8]? ){0}

    (?<castle>         O-O(-O)?     ){0}

    (?<normal>
      \g<piece>?
      \g<disambiguation>
      \g<capture>?
      \g<destination>
      \g<promotion>?
    ){0}

    \A (\g<castle> | \g<normal>) \g<check>? \z
  /x.freeze

  # @param move [String] the move in SAN
  # @param player [Symbol] the player making the move
  # @example
  #   PGN::Move.new("e4", :white)
  #
  def initialize(move, player)
    self.player = player
    self.san    = move

    match = move.match(SAN_REGEX)
    return  if match.nil?

    match.names.each do |name|
      send("#{name}=", match[name]) if respond_to?(name)
    end
  end

  def piece=(val)
    return if san.match('O-O')

    val ||= 'P'
    @piece = black? ? val.downcase : val
  end

  def promotion=(val)
    if val
      val.downcase! if black?
      @promotion = val.delete('=')
    end
  end

  def capture=(val)
    @capture = !!val
  end

  def disambiguation=(val)
    @disambiguation = (val == '' ? nil : val)
  end

  def castle=(val)
    if val
      @castle = 'K' if val == 'O-O'
      @castle = 'Q' if val == 'O-O-O'
      @castle.downcase! if black?
    end
  end

  # @return [Boolean] whether the move results in check
  #
  def check?
    check == '+'
  end

  # @return [Boolean] whether the move results in checkmate
  #
  def checkmate?
    check == '#'
  end

  # @return [Boolean] whether it's white's turn
  #
  def white?
    player == :white
  end

  # @return [Boolean] whether it's black's turn
  #
  def black?
    player == :black
  end

  # @return [Boolean] whether the piece being moved is a pawn
  #
  def pawn?
    %w[P p].include?(piece)
  end
end

#san ⇒ String

Returns the move string.

Examples:

move1.san #=> "O-O-O+"
move2.san #=> "Raxe1"
move3.san #=> "e8=Q#"

Returns:

  • (String) —

    the move string



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# File 'lib/pgn/move.rb', line 59

class Move
  attr_accessor :san, :player
  attr_accessor :piece, :destination, :promotion, :check, :capture, :disambiguation, :castle
  # A regular expression for matching moves in standard algebraic
  # notation
  #
  SAN_REGEX = /
    (?<piece>          [BKNQR]      ){0}
    (?<destination>    [a-h][1-8]   ){0}
    (?<promotion>      =[BNQR]      ){0}
    (?<check>          [#+]         ){0}
    (?<capture>        x            ){0}
    (?<disambiguation> [a-h]?[1-8]? ){0}

    (?<castle>         O-O(-O)?     ){0}

    (?<normal>
      \g<piece>?
      \g<disambiguation>
      \g<capture>?
      \g<destination>
      \g<promotion>?
    ){0}

    \A (\g<castle> | \g<normal>) \g<check>? \z
  /x.freeze

  # @param move [String] the move in SAN
  # @param player [Symbol] the player making the move
  # @example
  #   PGN::Move.new("e4", :white)
  #
  def initialize(move, player)
    self.player = player
    self.san    = move

    match = move.match(SAN_REGEX)
    return  if match.nil?

    match.names.each do |name|
      send("#{name}=", match[name]) if respond_to?(name)
    end
  end

  def piece=(val)
    return if san.match('O-O')

    val ||= 'P'
    @piece = black? ? val.downcase : val
  end

  def promotion=(val)
    if val
      val.downcase! if black?
      @promotion = val.delete('=')
    end
  end

  def capture=(val)
    @capture = !!val
  end

  def disambiguation=(val)
    @disambiguation = (val == '' ? nil : val)
  end

  def castle=(val)
    if val
      @castle = 'K' if val == 'O-O'
      @castle = 'Q' if val == 'O-O-O'
      @castle.downcase! if black?
    end
  end

  # @return [Boolean] whether the move results in check
  #
  def check?
    check == '+'
  end

  # @return [Boolean] whether the move results in checkmate
  #
  def checkmate?
    check == '#'
  end

  # @return [Boolean] whether it's white's turn
  #
  def white?
    player == :white
  end

  # @return [Boolean] whether it's black's turn
  #
  def black?
    player == :black
  end

  # @return [Boolean] whether the piece being moved is a pawn
  #
  def pawn?
    %w[P p].include?(piece)
  end
end

Instance Method Details

#black? ⇒ Boolean

Returns whether it’s black’s turn.

Returns:

  • (Boolean) —

    whether it’s black’s turn



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# File 'lib/pgn/move.rb', line 153

def black?
  player == :black
end

#check? ⇒ Boolean

Returns whether the move results in check.

Returns:

  • (Boolean) —

    whether the move results in check



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# File 'lib/pgn/move.rb', line 135

def check?
  check == '+'
end

#checkmate? ⇒ Boolean

Returns whether the move results in checkmate.

Returns:

  • (Boolean) —

    whether the move results in checkmate



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# File 'lib/pgn/move.rb', line 141

def checkmate?
  check == '#'
end

#pawn? ⇒ Boolean

Returns whether the piece being moved is a pawn.

Returns:

  • (Boolean) —

    whether the piece being moved is a pawn



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# File 'lib/pgn/move.rb', line 159

def pawn?
  %w[P p].include?(piece)
end

#white? ⇒ Boolean

Returns whether it’s white’s turn.

Returns:

  • (Boolean) —

    whether it’s white’s turn



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# File 'lib/pgn/move.rb', line 147

def white?
  player == :white
end