std:: uses_allocator <std::function>

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plus <> (C++14)
minus <> (C++14)
negate <> (C++14)
multiplies <> (C++14)
divides <> (C++14)
modulus <> (C++14)
bit_and <> (C++14)
bit_or <> (C++14)
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bit_xor <> (C++14)

equal_to <> (C++14)
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greater <> (C++14)
less <> (C++14)
greater_equal <> (C++14)
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Old binders and adaptors

unary_function ( until C++17* )
binary_function ( until C++17* )
ptr_fun ( until C++17* )
pointer_to_unary_function ( until C++17* )
pointer_to_binary_function ( until C++17* )
mem_fun ( until C++17* )
mem_fun_t mem_fun1_t const_mem_fun_t const_mem_fun1_t ( until C++17* ) ( until C++17* ) ( until C++17* ) ( until C++17* )
not1 ( until C++20* )
not2 ( until C++20* )

binder1st binder2nd ( until C++17* ) ( until C++17* )
bind1st bind2nd ( until C++17* ) ( until C++17* )

mem_fun_ref ( until C++17* )
mem_fun_ref_t mem_fun1_ref_t const_mem_fun_ref_t const_mem_fun1_ref_t ( until C++17* ) ( until C++17* ) ( until C++17* ) ( until C++17* )
unary_negate ( until C++20* )
binary_negate ( until C++20* )

Defined in header `<functional>`
template < class R, class ... ArgTypes , class Alloc > struct uses_allocator < std:: function < R ( ArgTypes... ) > , Alloc > : std:: true_type { } ;		(since C++11) (until C++17)

This specialization of std::uses_allocator informs other library components that all objects of type std::function support uses-allocator construction , even though they do not have a nested allocator_type .

Notes

std::function 's allocator support was poorly specified and inconsistently implemented. Some implementations do not support uses-allocator construction at all, some provide the needed constructor overloads but ignore the supplied allocator argument, and some provide the overloads and use the supplied allocator for construction but not when the std::function is reassigned. As a result, allocator support was removed in C++17.

Inherited from std:: integral_constant

Member constants

value

[static]

true
(public static member constant)

Member functions

operator bool	converts the object to bool , returns value (public member function)
operator() (C++14)	returns value (public member function)

Member types

Type	Definition
`value_type`	bool
`type`	std:: integral_constant < bool , value >

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Non-member functions
operator== operator!= (until C++20)
swap (std::function)
Helper classes
uses_allocator <std::function> (until C++17)
Deduction guides (C++17)