std::ranges:: all_of, std::ranges:: any_of, std::ranges:: none_of

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All names in this menu belong to namespace std::ranges
Non-modifying sequence operations
Modifying sequence operations
Partitioning operations
Sorting operations
Binary search operations (on sorted ranges)
Set operations (on sorted ranges)
Heap operations
Minimum/maximum operations
Permutation operations
Fold operations
Operations on uninitialized storage
Return types
Defined in header <algorithm>
Call signature
template < std:: input_iterator I, std:: sentinel_for < I > S,

class Proj = std:: identity ,
std:: indirect_unary_predicate < std :: projected < I, Proj >> Pred >
constexpr bool

all_of ( I first, S last, Pred pred, Proj proj = { } ) ;
(1) (since C++20)
template < ranges:: input_range R, class Proj = std:: identity ,

std:: indirect_unary_predicate <
std :: projected < ranges:: iterator_t < R > ,Proj >> Pred >
constexpr bool

all_of ( R && r, Pred pred, Proj proj = { } ) ;
(2) (since C++20)
template < std:: input_iterator I, std:: sentinel_for < I > S,

class Proj = std:: identity ,
std:: indirect_unary_predicate < std :: projected < I, Proj >> Pred >
constexpr bool

any_of ( I first, S last, Pred pred, Proj proj = { } ) ;
(3) (since C++20)
template < ranges:: input_range R, class Proj = std:: identity ,

std:: indirect_unary_predicate <
std :: projected < ranges:: iterator_t < R > ,Proj >> Pred >
constexpr bool

any_of ( R && r, Pred pred, Proj proj = { } ) ;
(4) (since C++20)
template < std:: input_iterator I, std:: sentinel_for < I > S,

class Proj = std:: identity ,
std:: indirect_unary_predicate < std :: projected < I, Proj >> Pred >
constexpr bool

none_of ( I first, S last, Pred pred, Proj proj = { } ) ;
(5) (since C++20)
template < ranges:: input_range R, class Proj = std:: identity ,

std:: indirect_unary_predicate <
std :: projected < ranges:: iterator_t < R > ,Proj >> Pred >
constexpr bool

none_of ( R && r, Pred pred, Proj proj = { } ) ;
(6) (since C++20)
1) Checks if unary predicate pred returns true for all elements in the range [ first , last ) (after projecting with the projection proj ).
3) Checks if unary predicate pred returns true for at least one element in the range [ first , last ) (after projecting with the projection proj ).
5) Checks if unary predicate pred returns true for no elements in the range [ first , last ) (after projecting with the projection proj ).
2,4,6) Same as (1,3,5) , but uses r as the source range, as if using ranges:: begin ( r ) as first and ranges:: end ( r ) as last .

The function-like entities described on this page are algorithm function objects (informally known as niebloids ), that is:

Parameters

first, last - the range of the elements to examine
r - the range of the elements to examine
pred - predicate to apply to the projected elements
proj - projection to apply to the elements

Return value

1,2) true if std:: invoke ( pred, std:: invoke ( proj, * i ) ) ! = false for every iterator i in the range, false otherwise. Returns true if the range is empty.
3,4) true if std:: invoke ( pred, std:: invoke ( proj, * i ) ) ! = false for at least one iterator i in the range, false otherwise. Returns false if the range is empty.
5,6) true if std:: invoke ( pred, std:: invoke ( proj, * i ) ) == false for every iterator i in the range, false otherwise. Returns true if the range is empty.

See also Notes below.

Complexity

At most last - first applications of the predicate and the projection.

Possible implementation

all_of (1,2) 
struct all_of_fn
{
    template<std::input_iterator I, std::sentinel_for<I> S, class Proj = std::identity,
             std::indirect_unary_predicate<std::projected<I, Proj>> Pred>
    constexpr bool operator()(I first, S last, Pred pred, Proj proj = {}) const
    {
        return ranges::find_if_not(first, last, std::ref(pred), std::ref(proj)) == last;
    }
 
    template<ranges::input_range R, class Proj = std::identity,
             std::indirect_unary_predicate<
                 std::projected<ranges::iterator_t<R>,Proj>> Pred>
    constexpr bool operator()(R&& r, Pred pred, Proj proj = {}) const
    {
        return operator()(ranges::begin(r), ranges::end(r),
                          std::ref(pred), std::ref(proj));
    }
};
 
inline constexpr all_of_fn all_of;
any_of (3,4) 
struct any_of_fn
{
    template<std::input_iterator I, std::sentinel_for<I> S, class Proj = std::identity,
             std::indirect_unary_predicate<std::projected<I, Proj>> Pred>
    constexpr bool operator()(I first, S last, Pred pred, Proj proj = {}) const
    {
        return ranges::find_if(first, last, std::ref(pred), std::ref(proj)) != last;
    }
 
    template<ranges::input_range R, class Proj = std::identity,
             std::indirect_unary_predicate<
                 std::projected<ranges::iterator_t<R>,Proj>> Pred>
    constexpr bool operator()(R&& r, Pred pred, Proj proj = {}) const
    {
        return operator()(ranges::begin(r), ranges::end(r),
                          std::ref(pred), std::ref(proj));
    }
};
 
inline constexpr any_of_fn any_of;
none_of (5,6) 
struct none_of_fn
{
    template<std::input_iterator I, std::sentinel_for<I> S, class Proj = std::identity,
             std::indirect_unary_predicate<std::projected<I, Proj>> Pred>
    constexpr bool operator()(I first, S last, Pred pred, Proj proj = {}) const
    {
        return ranges::find_if(first, last, std::ref(pred), std::ref(proj)) == last;
    }
 
    template<ranges::input_range R, class Proj = std::identity,
             std::indirect_unary_predicate<
                 std::projected<ranges::iterator_t<R>,Proj>> Pred>
    constexpr bool operator()(R&& r, Pred pred, Proj proj = {}) const
    {
        return operator()(ranges::begin(r), ranges::end(r),
                          std::ref(pred), std::ref(proj));
    }
};
 
inline constexpr none_of_fn none_of;

Notes

The return value represented in the form of the Truth table is:

input range contains
all true ,
none false
some true ,
some false
none true ,
all false
none true ,
none false
(empty range)
1,2) all_of true false false true
3,4) any_of true true false false
5,6) none_of false false true true

Example

Run this code 
#include <algorithm>
#include <functional>
#include <iostream>
#include <iterator>
#include <numeric>
#include <vector>
 
namespace ranges = std::ranges;
 
constexpr bool some_of(auto&& r, auto&& pred) // some but not all
{
    return not (ranges::all_of(r, pred) or ranges::none_of(r, pred));
}
 
constexpr auto w = {1, 2, 3};
static_assert(!some_of(w, [](int x) { return x < 1; }));
static_assert( some_of(w, [](int x) { return x < 2; }));
static_assert(!some_of(w, [](int x) { return x < 4; }));
 
int main()
{
    std::vector<int> v(10, 2);
    std::partial_sum(v.cbegin(), v.cend(), v.begin());
    std::cout << "Among the numbers: ";
    ranges::copy(v, std::ostream_iterator<int>(std::cout, " "));
    std::cout << '\n';
 
    if (ranges::all_of(v.cbegin(), v.cend(), [](int i) { return i % 2 == 0; }))
        std::cout << "All numbers are even\n";
 
    if (ranges::none_of(v, std::bind(std::modulus<int>(), std::placeholders::_1, 2)))
        std::cout << "None of them are odd\n";
 
    auto DivisibleBy = [](int d)
    {
        return [d](int m) { return m % d == 0; };
    };
 
    if (ranges::any_of(v, DivisibleBy(7)))
        std::cout << "At least one number is divisible by 7\n";
}

Output: 

Among the numbers: 2 4 6 8 10 12 14 16 18 20
All numbers are even
None of them are odd
At least one number is divisible by 7

See also

(C++11) (C++11) (C++11)
checks if a predicate is true for all, any or none of the elements in a range
(function template)
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