Message Sending
bankBalance
and its three methods, Deposit
, Withdraw
, and Balance
:
bankBalance := { total: 0, Deposit: func(amount) begin self.total := self.total + amount; end, Withdraw:func(amount) begin self.total := self.total - amount; end, Balance: func() return self.total, };To send messages to these various methods requires no more than
bankBalance:Deposit(50); bankBalance:Withdraw(20); bankBalance:Balance(); 30As each of the three methods executes,
self
is the bankBalance
frame; it is the frame to which each message is sent. Thus, self.total
is the total
in the bankBalance
frame.
An online version of Programming for the Newton using Macintosh, 2nd ed. ©1996, 1994, Julie McKeehan and Neil Rhodes.
Last modified: 1 DEC 1996