WPILibC++
2019.3.1

CRTP base class which implements the entire standard iterator facade in terms of a minimal subset of the interface. More...
#include <iterator.h>
Classes  
class  ReferenceProxy 
A proxy object for computing a reference via indirecting a copy of an iterator. More...  
Public Member Functions  
DerivedT  operator+ (DifferenceTypeT n) const 
DerivedT  operator (DifferenceTypeT n) const 
DerivedT &  operator++ () 
DerivedT  operator++ (int) 
DerivedT &  operator () 
DerivedT  operator (int) 
bool  operator!= (const DerivedT &RHS) const 
bool  operator> (const DerivedT &RHS) const 
bool  operator<= (const DerivedT &RHS) const 
bool  operator>= (const DerivedT &RHS) const 
PointerT  operator> () 
PointerT  operator> () const 
ReferenceProxy  operator[] (DifferenceTypeT n) 
ReferenceProxy  operator[] (DifferenceTypeT n) const 
Protected Types  
enum  { IsRandomAccess, IsBidirectional } 
Friends  
DerivedT  operator+ (DifferenceTypeT n, const DerivedT &i) 
CRTP base class which implements the entire standard iterator facade in terms of a minimal subset of the interface.
Use this when it is reasonable to implement most of the iterator functionality in terms of a core subset. If you need special behavior or there are performance implications for this, you may want to override the relevant members instead.
Note, one abstraction that this does not provide is implementing subtraction in terms of addition by negating the difference. Negation isn't always information preserving, and I can see very reasonable iterator designs where this doesn't work well. It doesn't really force much added boilerplate anyways.
Another abstraction that this doesn't provide is implementing increment in terms of addition of one. These aren't equivalent for all iterator categories, and respecting that adds a lot of complexity for little gain.
Classes wishing to use iterator_facade_base
should implement the following methods:
Forward Iterators: (All of the following methods)
Bidirectional Iterators: (All methods of forward iterators, plus the following)
Randomaccess Iterators: (All methods of bidirectional iterators excluding the following)