Cycle.opSlice
auto opSlice(size_t i, size_t j) nothrow @safeditto
inout(typeof(this)) opSlice(size_t i, DollarToken) nothrow inout @safeditto
auto opSlice(size_t i, size_t j) nothrow @safeditto
inout(typeof(this)) opSlice(size_t i, DollarToken) nothrow inout @safeditto