ruby - Object containing an array going to nil -
i have class deck represents array of 81 cards when try use getter functions on card in array gives error undefined method getcolor nil:nilclass (nomethoderror) assume means in array equals nil.
i trying figure out how set deck class can return card using getcard function , use card getter methods obtain values of individual card.
class card def initialize id, symbol, color, shading, number @cardid = id #0-80 unique each indivdual card in deck @cardsymbol = symbol # 0 = diamond 1 = squigly 2 = oval @cardcolor = color # 0 = green 1 = blue 2 = pink @cardshading = shading # 0 = none 1 = lines 2 = solid @cardnumber = number #number of symbols on card end def getid @cardid end def getsymbol @cardsymbol end def getcolor @cardcolor end def getshading @cardshading end def getnumber @cardnumber end end class deck def initialize @deck = array.new(81) @carddealt = array.new(81) end def addcardstodeck cardid = 0 symbol = 0 color = 0 shading = 0 number = 0 while cardid < 80 if symbol > 2 symbol = 0 color = color + 1 elsif color > 2 color = 0 shading = shading + 1 elsif shading > 2 shading = 0 number = number + 1 else symbol = symbol + 1 end card = card.new(cardid, symbol, color, shading, number) cardid = cardid + 1 @deck[cardid] = @card end end def getcard cardid @deck[cardid] end end setdeck = deck.new setdeck.addcardstodeck card0 = setdeck.getcard(0) puts "color #{card0.getcolor}"
the lines
card = card.new(cardid, symbol, color, shading, number) cardid = cardid + 1 @deck[cardid] = @card are problem. note how local variable card set in first line, while uninitialized instance variable @card used in third. sets entries nil.
another issue incrementing cardid before using index. set card 0 slot 1 etc. classic "one off" error.
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