Where can I learn more about mx files? In particular, in the following code, it looks like @2 is derived from the type expands this into a multitude of type specific functions. I can't figure out what @3 is. Is there a list of these? SORTfndlast_@2(BAT *b, ptr v) { BUN diff, end = BUNlast(b), cur = end; BUN lo = BUNfirst(b), hi = end; int cmp = 1; BATiter bi = bat_iterator(b); if (lo >= hi || @3_CMP(BUNt@1(bi, cur - 1), v, @4)<=0) { /* shortcut: if BAT is empty or last (and hence all) tail * value is <= v, we're done. */ return cur; } while (lo < hi) { BUN mid = (lo + hi) >> 1; cur = mid; cmp = @3_CMP(BUNt@1(bi, cur), v, @4); if (cmp < 0) { lo = ++mid; cur++; } else if (cmp > 0) { hi = mid; } else { break; } } if (cmp == 0 && b->tkey == 0) { /* shift over multiple equals */ for(diff = (end-cur)>>1; diff; diff >>= 1) { while ((cur+diff) < end && @3_EQ(BUNt@1(bi, cur+diff), v, @4)) cur += diff; } } if (cmp == 0) cur++; return cur; }