![Optional Options [You Don’t Have to Choose Any]](arrow-left.gif){kind=icon}
An ellipsis (...) means that you can repeat the last unit as many times as you like. In this syntax statement, buy is a required keyword:
buy thing = price [cash | check | credit]
[, thing = price [cash | check | credit] ]...
You must buy at least one thing and give its price. You may choose a method of payment: one of the items enclosed in square brackets. You may also choose to buy additional things: as many of them as you like. For each thing you buy, give its name, its price, and (optionally) a method of payment.
