void bubble(alias less = "a < b", Range)(Range datas) {
    import std.functional;
    alias binaryFun!(less) lessFun;

    size_t lastSwap = datas.length;
    foreach(size_t i, ref a; datas) {
        import std.range;
        import std.array;
        pragma(msg, typeof(datas));
        datas.popFront;

        auto previous = chunks(datas.save, lastSwap - i);
        if(current.empty) break;

        auto current = previous.save;
        current.popFront();
        if(current.empty) break;

        // Args are reversed so i have the value we want to assign to lastSwap;
        foreach(size_t i, ref b, ref a; lockstep(current, previous)) {
            if(lessFun(b, a)) {
                import std.algorithm;
                swap(b, a);

                lastSwap = i;
            }
        }
    }
}

void main() {
    bubble([1, 2, 3, 0]);
}

->

int[]
sort/bubble.d(12): Error: undefined identifier module bubble.popFront
sort/bubble.d(14): Error: undefined identifier module bubble.save
sort/bubble.d(15): Error: undefined identifier current