InputRange.opApply
int opApply(scope int delegate(E))foreach iteration uses opApply, since one delegate call per loop iteration is faster than three virtual function calls.
int opApply(scope int delegate(size_t, E))Ditto
int opApply(scope int delegate(E))foreach iteration uses opApply, since one delegate call per loop iteration is faster than three virtual function calls.
int opApply(scope int delegate(size_t, E))Ditto