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std::ranges::drop_while_view<V,Pred>::pred

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Ranges library
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(C++23)

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(until C++23)(C++23)


 
 
constexpr const Pred& pred() const;
(since C++20)

Returns a reference to the stored predicate.

If *this does not store a predicate (e.g. an exception is thrown on the assignment to *this, which copy-constructs or move-constructs a Pred), the behavior is undefined.

[edit] Parameters

(none)

[edit] Return value

A reference to the stored predicate.

[edit] Example

#include <array>
#include <iomanip>
#include <iostream>
#include <ranges>
 
int main()
{
    constexpr std::array data{0, -1, -2, 3, 1, 4, 1, 5};
 
    auto view = std::ranges::drop_while_view
    {
        data, [](int x) { return x <= 0; }
    };
 
    std::cout << std::boolalpha;
    for (int x : data)
        std::cout << "predicate(" << std::setw(2) << x << ") : "
                  << view.pred()(x) << '\n';
}

Output:

predicate( 0) : true
predicate(-1) : true
predicate(-2) : true
predicate( 3) : false
predicate( 1) : false
predicate( 4) : false
predicate( 1) : false
predicate( 5) : false