std::latch::latch - cppreference.com

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std::latch

Member functions
latch::latch
latch::~latch
latch::count_down
latch::try_wait
latch::wait
latch::arrive_and_wait
Constants
latch::max

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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.