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Okay, so we've got our BankAccount class
all set up.

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And we've get credits, debits, and
transactions going on.

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So it would be nice to be able to see what
our balance is.

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So let's go ahead and write a method that
calculates the balance for

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us by looping through the transactions.

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So we know that transactions is an array.

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And in the Ruby Loops course,

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we learned about iterating through arrays
with the each method.

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Let's go ahead and use the each method to
iterate over the transactions and

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add up the balance.

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So, we can say @transactions.each do.

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|transaction|

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This will iterate over the @transactions
array and

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pass each item into this little code
block.

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And now we'll create a local variable,
which we're just gonna call balance.

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And then we'll add on to the balance in
each transaction.

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So, we'll say the balance is equal to
whatever it was before,

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plus the amount of this transaction.

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[SOUND] And then, we can return the
balance.

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[BLANK_AUDIO]

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Now we know that the transaction amount is
gonna be positive or negative.

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We know that because we're going to be
calling the credit and

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debit methods each time we add on to the
transactions.

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So we know that when there's a debit, this
goes in as a negative amount.

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And credits go in as a positive amount.

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Therefore, adding on to the balance will
work as we expect it to,

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because adding a negative number is the
same as subtraction.

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So now instead of this inspect method,
let's go ahead and print out the balance.

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And that functions exactly as we

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expect it to by returning 60.

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Now what would happen if we made this 0.0?

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Well, it prints out 60.0.

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Now if we wanted this to print out like
currency,

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say having 60.0 and instead we want 60.00,

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we can use a method called sprintf to
format this particular string.

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You can read the documentation for this if
you'd like to find out a little bit more.

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The string that we need to use, is a
percent,

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a zero, a dot, a two, and an f.

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Which means it's going to print this
floating point number to two decimals.

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So if we run this again, it prints out
60.00 just like we expect.

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Now that we have this balance method all
set up, let's go ahead and

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override the to string method to print
that all out.

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So to_s, we'll say the name is the name
that we initialized the class with.

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And the balance is the balance.

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And you know what, let's go ahead and call
balance just like we do here.

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[BLANK_AUDIO]

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Now this is a little tricky,

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because we're doing string interpolation
inside of another string.

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So we can go down here.

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And just print out the bank account.

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So now, it says name Jason and the balance
is 60.00.

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In our next video, we'll be printing out a
formatted register.