std::mergeable
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 C++ 
 Feature test macros (C++20)
 Concepts library (C++20)
 Metaprogramming library (C++11)
 Ranges library (C++20)
 Filesystem library (C++17)
 Concurrency support library (C++11)
 Execution control library (C++26)
Iterator library 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
   
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
 
 
  
 
 
 
 
 
  
(C++20)
(C++20)
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(C++20)(C++20)
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(C++20)(C++20)(C++20)(C++23)(C++20)(C++20)
(deprecated in C++17)
(C++20)
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(C++20)(C++20)
  (C++20)
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(C++14)
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(C++20)(C++20)
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  Defined in header 
 
 
<iterator> 
 template< class I1, class I2, class Out, class Comp = ranges::less,
 
 (since C++20) 
          class Proj1 = std::identity, class Proj2 = std::identity >
concept mergeable =
    std::input_iterator <I1> &&
    std::input_iterator <I2> &&
    std::weakly_incrementable <Out> &&
    std::indirectly_copyable <I1, Out> &&
    std::indirectly_copyable <I2, Out> &&
    std::indirect_strict_weak_order <Comp,
                                    std::projected <I1, Proj1>,
The mergeable concept specifies the requirements for algorithms that merge two input ranges into a single output range according to the strict weak ordering imposed by Comp.
[edit] Semantic requirements
mergeable is modeled only if all concepts it subsumes are modeled.