propBuySizeNotExceeded :: OrderBuy -> Book -> Bool
propBuySizeNotExceeded buy book = sum (map tradeSize trades) <= bSize buy
  where (_, trades) = processBuy book buy
propBuySizeNotExceeded :: OrderBuy -> Book -> Bool
propBuySizeNotExceeded buy book = sum (map tradeSize trades) <= bSize buy
  where (_, trades) = processBuy book buy
propBuySizeNotExceeded buy book = sum (map tradeSize trades) <= bSize buy
  where (_, trades) = processBuy book buy