sidef/scripts/accumulator_factory_oo.sf

#!/usr/bin/ruby

class Accumulator (sum) {
    method add1(num) {
        sum += num;
    }

    method add2(num) {
        self{:sum} += num;
    }

    method add3(num) {
        self.sum += num;
    }

    method +(num) {
        self.sum = (sum + num);
    }
}

var x = Accumulator(1);

x.add1(1.25);
x.add2(1.875);
x.add3(1.875);

Accumulator(3);             # create another accumulator

say (x + 2.3);              # prints: 8.3