Games_Chess
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Packages:
Games_Chess


Classes:
Games_Chess
Games_Chess_Losers
Games_Chess_Standard
Files:
Chess.php
HTMLChess.php
Losers.php
Standard.php

Class: Games_Chess

Source Location: /Games_Chess-0.7.0/Chess.php

Class Overview




ABSTRACT parent class - use Games_Chess_Standard for a typical  chess game















Methods















Child classes:






Games_Chess_Standard

	
Standard chess game









Inherited Variables





Inherited Methods














Class Details



[line 258]

ABSTRACT parent class - use Games_Chess_Standard for a typical  chess game
Error Constants  This class contains a few public methods that are the only thing most  users of the package will ever need.  Protected methods are available  for usage by child classes, and it is expected that all child classes  will implement certain protected methods used by the utility methods in  this class.
Public API methods used are:
Game-related methods
  • resetGame(): in order to start a new game (pass a FEN for a starting
   position)
  • blankBoard(): in order to start with an empty chessboard
  • addPiece(): Use to add pieces one at a time to the board
  • moveSAN(): Use to move pieces based on their SAN (Qa3, exd5, etc.)
  • moveSquare(): Use to move pieces based on their square (a2 -> a3
   for Qa3, e4 -> d5 for exd5, etc.)
  Game state methods:
  • inCheck(): Use to determine the presence of check
  • inCheckMate(): Use to determine a won game
  • inStaleMate(): Use to determine presence of stalemate draw
  • in50MoveDraw(): Use to determine presence of 50-move rule draw
  • inRepetitionDraw(): Use to determine presence of a draw by repetition
  • inStaleMate(): Use to determine presence of stalemate draw
  • inDraw(): Use to determine if any forced draw condition exists
  Game data methods:
  • renderFen(): Use to retrieve a FEN representation of the
   current chessboard position, in order to transfer to another chess program
  • toArray(): Use to retrieve a literal representation of the
   current chessboard position, in order to display as HTML or some other
   format for the user
  • getMoveList(): Use to retrieve the list of SAN moves for this game




[ Top ]








Method Detail



	
	
addPiece   [line 755]

	

    

    

		void addPiece(
W|B
$color, P|N|K|Q|R|B
$type, string
$square)
    

    


	
		Add a piece to the chessboard
Must be overridden in child classes


    

  • Abstract: 
    • 







	
Overridden in child classes as:

		

	
Games_Chess_Standard::addPiece()

		
Add a piece to the chessboard

	

	


        
Parameters:

    

    

          

        W|B  
        $color  
        — 
        Color of piece
      

          

        P|N|K|Q|R|B  
        $type  
        — 
        Piece type
      

          

        string  
        $square  
        — 
        algebraic location of piece
      

        

    


        
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blankBoard   [line 335]

	

    

    

		void blankBoard(
)
    

    


	
		Create a blank chessboard with no pieces on it



	
Overridden in child classes as:

		

	
Games_Chess_Standard::blankBoard()

		
Set up a blank chess board

	

	


        
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canCastleKingside   [line 805]

	

    

    

		boolean canCastleKingside(
)
    

    


	
		Determine legality of kingside castling




        
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canCastleQueenside   [line 815]

	

    

    

		boolean canCastleQueenside(
)
    

    


	
		Determine legality of queenside castling




        
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commitTransaction   [line 2225]

	

    

    

		void commitTransaction(
)
    

    


	
		Remove any possibility of undo.




        
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gameOver   [line 481]

	

    

    

		W|B|D|false gameOver(
)
    

    


	
		


    

  • Return: winner of game, or draw, or false if still going
    • 







	
Overridden in child classes as:

		

	
Games_Chess_Losers::gameOver()

		

	

	


        
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getDiagonalColor   [line 2023]

	

    

    

		void getDiagonalColor(

$square)
    

    


	
		



        
Parameters:

    

    

          

          
        $square  
        — 
        
      

        

    


        
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getMessage   [line 2084]

	

    

    

		string getMessage(
integer
$code, array
$extra)
    

    


	
		Get an error message from the code
Future versions of this method will be multi-language




        
Parameters:

    

    

          

        integer  
        $code  
        — 
        Error code
      

          

        array  
        $extra  
        — 
        extra information to pass for error message creation
      

        

    


        
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getMoveList   [line 473]

	

    

    

		array getMoveList(
)
    

    


	
		Get the list of moves in Standard Algebraic Notation
Can be used to populate a PGN file.




        
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getPieceLocations   [line 1673]

	

    

    

		array|PEAR_Error getPieceLocations(
[W|B
$color = null])
    

    


	
		Get the location of all pieces on the board of a certain color
Default is the color that is about to move


    

  • Throws: GAMES_CHESS_ERROR_INVALID_COLOR
    • 








        
Parameters:

    

    

          

        W|B  
        $color  
        — 
        
      

        

    


        
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getPossibleBishopMoves   [line 1729]

	

    

    

		array getPossibleBishopMoves(
string
$square, [W|B
$color = null])
    

    


	
		Get all legal Bishop moves (checking of the king is not taken into account)




        
Parameters:

    

    

          

        string  
        $square  
        — 
        [a-h][1-8] Location of piece
      

          

        W|B  
        $color  
        — 
        color of piece, or null to use current piece to move
      

        

    


        
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getPossibleKingMoves   [line 1979]

	

    

    

		array getPossibleKingMoves(
string
$square, [W|B
$color = null], [
$returnCastleMoves = true])
    

    


	
		Get all legal King moves (checking of the king is not taken into account)


    

  • Since: 0.7alpha castling is possible by moving the king to the destination square
    • 








        
Parameters:

    

    

          

        string  
        $square  
        — 
        [a-h][1-8] Location of piece
      

          

        W|B  
        $color  
        — 
        color of piece, or null to use current piece to move
      

          

          
        $returnCastleMoves  
        — 
        
      

        

    


        
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getPossibleKnightMoves   [line 1704]

	

    

    

		array getPossibleKnightMoves(
string
$square, [W|B
$color = null])
    

    


	
		Get all legal Knight moves (checking of the king is not taken into account)




        
Parameters:

    

    

          

        string  
        $square  
        — 
        [a-h][1-8] Location of piece
      

          

        W|B  
        $color  
        — 
        color of piece, or null to use current piece to move
      

        

    


        
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getPossibleMoves   [line 1328]

	

    

    

		array|PEAR_Error getPossibleMoves(
K|P|Q|R|B|N
$piece, string
$square, [B|W
$color = null], [boolean
$returnCastleMoves = true])
    

    


	
		Get a list of all possible theoretical squares a piece of this nature  and color could move to with the current board and game setup.
This method will return all valid moves without determining the presence  of check


    

  • Throws: GAMES_CHESS_ERROR_INVALID_COLOR
    • 

  • Throws: GAMES_CHESS_ERROR_INVALID_SQUARE
    • 

  • Throws: GAMES_CHESS_ERROR_INVALID_PIECE
    • 








        
Parameters:

    

    

          

        K|P|Q|R|B|N  
        $piece  
        — 
        Piece name
      

          

        string  
        $square  
        — 
        [a-h][1-8] algebraic location of the piece
      

          

        B|W  
        $color  
        — 
        color of the piece
      

          

        boolean  
        $returnCastleMoves  
        — 
        Whether to return shortcut king moves for castling
      

        

    


        
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getPossiblePawnMoves   [line 1898]

	

    

    

		array getPossiblePawnMoves(
string
$square, [W|B
$color = null], [
$enpassant = null])
    

    


	
		Get all legal Pawn moves (checking of the king is not taken into account)




        
Parameters:

    

    

          

        string  
        $square  
        — 
        [a-h][1-8] Location of piece
      

          

        W|B  
        $color  
        — 
        color of piece, or null to use current piece to move
      

          

          
        $enpassant  
        — 
        
      

        

    


        
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getPossibleQueenMoves   [line 1879]

	

    

    

		array getPossibleQueenMoves(
string
$square, [W|B
$color = null])
    

    


	
		Get all legal Queen moves (checking of the king is not taken into account)




        
Parameters:

    

    

          

        string  
        $square  
        — 
        [a-h][1-8] Location of piece
      

          

        W|B  
        $color  
        — 
        color of piece, or null to use current piece to move
      

        

    


        
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getPossibleRookMoves   [line 1804]

	

    

    

		array getPossibleRookMoves(
string
$square, [W|B
$color = null])
    

    


	
		Get all legal Rook moves (checking of the king is not taken into account)




        
Parameters:

    

    

          

        string  
        $square  
        — 
        [a-h][1-8] Location of piece
      

          

        W|B  
        $color  
        — 
        color of piece, or null to use current piece to move
      

        

    


        
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in50MoveDraw   [line 621]

	

    

    

		boolean in50MoveDraw(
)
    

    


	
		Determine whether any pawn move or capture has occurred in the past 50 moves




        
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inBasicDraw   [line 641]

	

    

    

		boolean inBasicDraw(
)
    

    


	
		Determine the presence of a basic draw as defined by FIDE rules
The rule states:  
 10.4

 The game is drawn when one of the following endings arises:
 (a) king against king;
 (b) king against king with only bishop or knight;
 (c) king and bishop against king and bishop, with both bishops
     on diagonals of the same colour.




        
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inCheckMate   [line 499]

	

    

    

		boolean inCheckMate(
[W|B
$color = null])
    

    


	
		Determine whether a side is in checkmate


    

  • Throws: GAMES_CHESS_ERROR_INVALID_COLOR
    • 








        
Parameters:

    

    

          

        W|B  
        $color  
        — 
        color of side to check, defaults to the current side
      

        

    


        
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inDraw   [line 577]

	

    

    

		boolean inDraw(
[W|B
$color = null])
    

    


	
		Determines the presence of a forced draw




        
Parameters:

    

    

          

        W|B  
        $color  
        — 
        
      

        

    


        
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inRepetitionDraw   [line 608]

	

    

    

		boolean inRepetitionDraw(
)
    

    


	
		Determine whether draw by repetition has happened
From FIDE rules:  
 10.10

 The game is drawn, upon a claim by the player having the move, when the
 same position, for the third time:
 (a) is about to appear, if he first writes the move on his
     scoresheet and declares to the arbiter his intention of making
     this move; or
 (b) has just appeared, the same player having the move each time.

 The position is considered the same if pieces of the same kind and
 colour occupy the same squares, and if all the possible moves of
 all the pieces are the same, including the rights to castle [at
 some future time] or to capture a pawn "en passant".
This class determines draw by comparing FENs rendered after every move




        
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inStaleMate   [line 541]

	

    

    

		boolean inStaleMate(
[W|B
$color = null])
    

    


	
		Determine whether a side is in stalemate


    

  • Throws: GAMES_CHESS_ERROR_INVALID_COLOR
    • 








        
Parameters:

    

    

          

        W|B  
        $color  
        — 
        color of the side to look at, defaults to the current side
      

        

    


        
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isError   [line 2201]

	

    

    

		boolean isError(
mixed
$err)
    

    


	
		Determines whether the data returned from a method is a PEAR-related
error class




        
Parameters:

    

    

          

        mixed  
        $err  
        — 
        
      

        

    


        
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isPromoteMove   [line 781]

	

    

    

		boolean isPromoteMove(
string
$from, string
$to)
    

    


	
		Determine whether moving a piece from one square to another requires
a pawn promotion


    

  • Return: true if the move represented by moving from $from to $to                  is a pawn promotion move
    • 








        
Parameters:

    

    

          

        string  
        $from  
        — 
        [a-h][1-8] location of the piece to move
      

          

        string  
        $to  
        — 
        [a-h][1-8] place to move the piece to
      

        

    


        
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moveSAN   [line 371]

	

    

    

		true|PEAR_Error moveSAN(
string
$move)
    

    


	
		Make a move from a Standard Algebraic Notation (SAN) format
SAN is just a normal chess move like Na4, instead of the English Notation,  like NR4




        
Parameters:

    

    

          

        string  
        $move  
        — 
        
      

        

    


        
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moveSquare   [line 457]

	

    

    

		true|PEAR_Error moveSquare(
string
$from, string
$to, [string
$promote = ''])
    

    


	
		Move a piece from one square to another, and mark the old square as empty




        
Parameters:

    

    

          

        string  
        $from  
        — 
        [a-h][1-8] square to move from
      

          

        string  
        $to  
        — 
        [a-h][1-8] square to move to
      

          

        string  
        $promote  
        — 
        piece to promote to, if this is a promotion move
      

        

    


        
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raiseError   [line 2069]

	

    

    

		PEAR_Error raiseError(
integer
$code, [array
$extra = array()])
    

    


	
		


    

  • Uses: PEAR::raiseError()
    • 








        
Parameters:

    

    

          

        integer  
        $code  
        — 
        error code from Chess.php
      

          

        array  
        $extra  
        — 
        associative array of additional error message data
      

        

    


        
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renderFen   [line 704]

	

    

    

		string renderFen(
[boolean
$include_moves = true])
    

    


	
		render the FEN notation for the current board




        
Parameters:

    

    

          

        boolean  
        $include_moves  
        — 
        private parameter, used to determine whether to include                 move number/ply count - this is used to keep track of                 positions for draw detection
      

        

    


        
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resetGame   [line 352]

	

    

    

		PEAR_Error|true resetGame(
[false|string
$fen = false])
    

    


	
		Create a new game with the starting position, or from the position  specified by $fen


    

  • Return: returns any errors thrown by _parseFen()
    • 








        
Parameters:

    

    

          

        false|string  
        $fen  
        — 
        
      

        

    


        
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rollbackTransaction   [line 2233]

	

    

    

		void rollbackTransaction(
)
    

    


	
		Undo any changes to state since startTransaction() was first used




        
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startTransaction   [line 2212]

	

    

    

		void startTransaction(
)
    

    


	
		Begin a chess piece transaction
Transactions are used to attempt moves that may be revoked later, especially  in methods like inCheckMate()




        
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toArray   [line 768]

	

    

    

		array toArray(
)
    

    


	
		Generate a representation of the chess board and pieces for use as a  direct translation to a visual chess board
Must be overridden in child classes


    

  • Abstract: 
    • 







	
Overridden in child classes as:

		

	
Games_Chess_Standard::toArray()

		
Generate a representation of the chess board and pieces for use as a

	

	


        
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toMove   [line 796]

	

    

    

		W|B toMove(
)
    

    


	
		


    

  • Return: return the color of the side to move (white or black)
    • 








        
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_convertSquareToSAN   [line 1223]

	

    

    

		string|PEAR_Error _convertSquareToSAN(
string
$from, string
$to, [string
$promote = ''])
    

    


	
		Convert a starting and ending algebraic square into SAN


    

  • Throws: GAMES_CHESS_ERROR_INVALID_SQUARE
    • 

  • Throws: GAMES_CHESS_ERROR_INVALID_PROMOTE
    • 

  • Throws: GAMES_CHESS_ERROR_NO_PIECE
    • 

  • Throws: GAMES_CHESS_ERROR_WRONG_COLOR
    • 

  • Throws: GAMES_CHESS_ERROR_CANT_MOVE_THAT_WAY
    • 

  • Access: protected
    • 








        
Parameters:

    

    

          

        string  
        $from  
        — 
        [a-h][1-8] square piece is on
      

          

        string  
        $to  
        — 
        [a-h][1-8] square piece moves to
      

          

        string  
        $promote  
        — 
        Q|R|B|N
      

        

    


        
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_getAllPieceLocations   [line 1693]

	

    

    

		array _getAllPieceLocations(
W|B
$color)
    

    


	
		Get the location of every piece on the board of color $color


    

  • Abstract: 
    • 

  • Access: protected
    • 







	
Overridden in child classes as:

		

	
Games_Chess_Standard::_getAllPieceLocations()

		
Get the location of every piece on the board of color $color

	

	


        
Parameters:

    

    

          

        W|B  
        $color  
        — 
        color of pieces to check
      

        

    


        
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_getCastleSquares   [line 1605]

	

    

    

		array _getCastleSquares(
string
$square)
    

    


	
		Get a list of all the squares a king could castle to on an empty board
WARNING: assumes valid input


    

  • Since: 0.7alpha
    • 

  • Access: protected
    • 








        
Parameters:

    

    

          

        string  
        $square  
        — 
        [a-h][1-8]
      

        

    


        
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_getDiagonalColor   [line 2013]

	

    

    

		B|W _getDiagonalColor(
string
$square)
    

    


	
		Return the color of a square (black or white)


    

  • Access: protected
    • 








        
Parameters:

    

    

          

        string  
        $square  
        — 
        [a-h][1-8]
      

        

    


        
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_getKingSquares   [line 1635]

	

    

    

		array _getKingSquares(
string
$square)
    

    


	
		Get a list of all the squares a king could move to on an empty board
WARNING: assumes valid input


    

  • Access: protected
    • 








        
Parameters:

    

    

          

        string  
        $square  
        — 
        [a-h][1-8]
      

        

    


        
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_getKnightSquares   [line 1555]

	

    

    

		array _getKnightSquares(
string
$square, [boolean
$returnFlatArray = false])
    

    


	
		Get all the squares a knight could move to on an empty board
WARNING: assumes valid input


    

  • Return: Returns an array of all the squares organized by compass                point, that a knight can go to.  These squares may be indexed                by any of WNW, NNW, NNE, ENE, ESE, SSE, SSW or WSW, unless                $returnFlatArray is true, in which case an array of squares                is returned
    • 

  • Access: protected
    • 








        
Parameters:

    

    

          

        string  
        $square  
        — 
        [a-h][1-8]
      

          

        boolean  
        $returnFlatArray  
        — 
        if true, simply returns an array of all squares
      

        

    


        
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_getQueenSquares   [line 1536]

	

    

    

		array _getQueenSquares(
string
$square, [boolean
$returnFlatArray = false])
    

    


	
		Get all the squares a queen could go to on a blank board
WARNING: assumes valid input


    

  • Return: combines contents of _getRookSquares() and                _getDiagonals()
    • 

  • Access: protected
    • 








        
Parameters:

    

    

          

        string  
        $square  
        — 
        [a-h][1-8]
      

          

        boolean  
        $returnFlatArray  
        — 
        if true, simply returns an array of all squares
      

        

    


        
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_getRookSquares   [line 1470]

	

    

    

		array _getRookSquares(
string
$square, [boolean
$returnFlatArray = false])
    

    


	
		Get the set of squares that are diagonals from this square on an empty board.
WARNING: assumes valid input


    

  • Return: 
    Format:
     array(
   'N' => array(square, square),
   'E' => array(square, square),
   'S' => array(square, square),
   'W' => array(square, square)
 )
    Think of the horizontal directions as on a map.  squares are listed with  closer squares first
    • 

  • Access: protected
    • 








        
Parameters:

    

    

          

        string  
        $square  
        — 
        [a-h][1-8]
      

          

        boolean  
        $returnFlatArray  
        — 
        if true, simply returns an array of all squares
      

        

    


        
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_moveAlgebraic   [line 830]

	

    

    

		void _moveAlgebraic(
string
$from, string
$to, [string
$promote = ''])
    

    


	
		Move a piece from one square to another, and mark the old square as empty
NO validation is performed, use moveSquare() for validation.


    

  • Access: protected
    • 








        
Parameters:

    

    

          

        string  
        $from  
        — 
        [a-h][1-8] square to move from
      

          

        string  
        $to  
        — 
        [a-h][1-8] square to move to
      

          

        string  
        $promote  
        — 
        piece to promote to, if this is a promotion move
      

        

    


        
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_parseMove   [line 854]

	

    

    

		array _parseMove(
string
$move)
    

    


	
		Parse out the segments of a move (minus any annotations)


    

  • Access: protected
    • 








        
Parameters:

    

    

          

        string  
        $move  
        — 
        
      

        

    


        
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_setupStartingPosition   [line 915]

	

    

    

		void _setupStartingPosition(
)
    

    


	
		Set up the board with the starting position
Must be overridden in child classes


    

  • Abstract: 
    • 

  • Access: protected
    • 







	
Overridden in child classes as:

		

	
Games_Chess_Standard::_setupStartingPosition()

		
Set up a starting position for a new chess game

	

	


        
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_validMove   [line 1101]

	

    

    

		true|PEAR_Error _validMove(
array
$move)
    

    


	
		Validate a move


    

  • Throws: GAMES_CHESS_ERROR_CK_PIECES_IN_WAY
    • 

  • Throws: GAMES_CHESS_ERROR_CANT_CK
    • 

  • Throws: GAMES_CHESS_ERROR_IN_CHECK
    • 

  • Throws: GAMES_CHESS_ERROR_CANT_CQ
    • 

  • Throws: GAMES_CHESS_ERROR_CQ_PIECES_IN_WAY
    • 

  • Throws: GAMES_CHESS_ERROR_STILL_IN_CHECK
    • 

  • Throws: GAMES_CHESS_ERROR_MOVE_WOULD_CHECK
    • 

  • Throws: GAMES_CHESS_ERROR_CANT_CAPTURE_OWN
    • 

  • Throws: GAMES_CHESS_ERROR_CASTLE_WOULD_CHECK
    • 

  • Access: protected
    • 







	
Overridden in child classes as:

		

	
Games_Chess_Losers::_validMove()

		
Validate a move

	

	


        
Parameters:

    

    

          

        array  
        $move  
        — 
        parsed move array from _parsedMove()
      

        

    


        
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		    Documentation generated on Mon, 11 Mar 2019 10:14:58 -0400 by phpDocumentor 1.4.4. PEAR Logo Copyright ©  PHP Group 2004.