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Ruby Ruby Objects and Classes Build a Bank Account Class Implement the balance Method

Posted by David Greenstein
David Greenstein
6,734 Points

Why do I have to use [:amount] instead of ["amount"] 

 def balance
    balance = 0
    @transactions.each do |transaction|
      balance += transaction["amount"]
    end
    return balance
  end
bank_account.rb 
class BankAccount
  attr_reader :name

  def initialize(name)
    @name = name
    @transactions = []
    add_transaction("Beginning Balance", 0)
  end

  def debit(description, amount)
    add_transaction(description, -amount)
  end

  def credit(description, amount)
    add_transaction(description, amount)
  end

  def add_transaction(description, amount)
    @transactions.push(description: description, amount: amount)
  end

  def balance
    balance = 0
    @transactions.each do |transaction|
      balance += transaction["amount"]
    end
    return balance
  end


end

1 Answer

Michael Hulet
Michael Hulet
47,912 Points
Michael Hulet
Michael Hulet
47,912 Points

Previously, the value you're looking for was added to the @transactions hash using the symbol :amount as a key, and not the string "amount". Thus, to reference it again, you'll have to use the symbol instead of the string, because doing @transactions[:amount] is entirely different from doing @transaction["amount"], as strings are not symbols and vice versa