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Start your free trialDavid Greenstein
6,734 PointsWhy are we able to do interpolation with balance here?
Why are we able to do interpolation with balance when its not an instance variable like name
def to_s
"Name: #{name},Balance: #{balance}"
end
class BankAccount
attr_reader :name
def initialize(name)
@name = name
@transactions = []
add_transaction("Beginning Balance", 0)
end
def balance
balance = 0
@transactions.each do |transaction|
balance += transaction[:amount]
end
balance
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 to_s
"Name: #{name},Balance: #{balance}"
end
end
1 Answer
Maciej Czuchnowski
36,441 PointsIt's still a method, so whatever that method returns, will be interpolated. Notice that instance variable @name by itself would have to be interpolated as #{@name}
in normal circumstances, but attr_reader :name
creates a method called name
, which simply returns the value of the instance variable @name
. So in both cases - name
and balance
- you're interpolating method return values.