# std::equal_to, not_equal_to, less, greater, less_equal, greater_equal(std::experimental::propagate_const)

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< cpp‎ | experimental‎ | propagate const

Defined in header `<experimental/propagate_const>` |  |
template<class T> struct equal_to< std::experimental::propagate_const <T>>; |  | (library fundamentals TS v2)
template<class T> struct not_equal_to< std::experimental::propagate_const <T>>; |  | (library fundamentals TS v2)
template<class T> struct less< std::experimental::propagate_const <T>>; |  | (library fundamentals TS v2)
template<class T> struct greater< std::experimental::propagate_const <T>>; |  | (library fundamentals TS v2)
template<class T> struct less_equal< std::experimental::propagate_const <T>>; |  | (library fundamentals TS v2)
template<class T> struct greater_equal< std::experimental::propagate_const <T>>; |  | (library fundamentals TS v2)

The standard comparison function objects are partially specialized for std::experimental::propagate_const <T>.

Let p.t_ denote the pointer-like object wrapped by a std::experimental::propagate_const <T> p, then given objects `p` and `q` of type std::experimental::propagate_const <T>, the following shall hold:

- std::equal_to < std::experimental::propagate_const <T>>()(p, q) == std::equal_to <T>()(p.t_, q.t_)
- std::not_equal_to < std::experimental::propagate_const <T>>()(p, q) == std::not_equal_to <T>()(p.t_, q.t_)
- std::less < std::experimental::propagate_const <T>>()(p, q) == std::less <T>()(p.t_, q.t_)
- std::greater < std::experimental::propagate_const <T>>()(p, q) == std::greater <T>()(p.t_, q.t_)
- std::less_equal < std::experimental::propagate_const <T>>()(p, q) == std::less_equal <T>()(p.t_, q.t_)
- std::greater_equal < std::experimental::propagate_const <T>>()(p, q) == std::greater_equal <T>()(p.t_, q.t_)

### Notes

These specializations ensure that when `T` is a pointer type, specializations of these class templates for std::experimental::propagate_const <T> yield a total order, even if the corresponding built-in operators do not.

### Example

| This section is incomplete Reason: no example

### See also

equal_to | function object implementing x == y (class template)
not_equal_to | function object implementing x != y (class template)
less | function object implementing x < y (class template)
greater | function object implementing x > y (class template)
less_equal | function object implementing x <= y (class template)
greater_equal | function object implementing x >= y (class template)

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