578. Time when right to foreclose arises depends on proviso for redemption.

So long as the mortgagor has a legal right of redemption there can be no foreclosure; but when the time for repayment of the loan is past, the right to commence foreclosure proceedings arises unless the mortgagee has by special stipulation postponed the right1. Consequently, the time when the right arises depends on the form of the proviso for redemption, if any