std::latch:: latch

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Concurrency support library
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this_thread namespace
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constexpr explicit latch ( std:: ptrdiff_t expected ) ;
(1) (since C++20)
latch ( const latch & ) = delete ;
(2) (since C++20)
1) Constructs a latch and initializes its internal counter. The behavior is undefined if expected is negative or greater than max() .
2) Copy constructor is deleted. latch is neither copyable nor movable.

Parameters

expected - the initial value of the internal counter

Exceptions

Throws nothing.