class box
    function __construct(public v) end
end

local i = new box(0)  -- any initial value will do here

local function sum(b, lo, hi, term)
    local temp = 0
    b.v = lo
    while b.v <= hi do
        temp += term()
        b.v += 1
    end
    return temp
end

local s = sum(i, 1, 100, || -> 1 / i.v)
print(s)