std::tuple_element<std::complex>

 

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gcd (C++17)	lcm (C++17)
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add_sat (C++26) sub_sat (C++26) saturate_cast (C++26)	mul_sat (C++26) div_sat (C++26)
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iota (C++11) ranges::iota (C++23) accumulate inner_product adjacent_difference partial_sum	reduce (C++17) transform_reduce (C++17) inclusive_scan (C++17) exclusive_scan (C++17) transform_inclusive_scan (C++17) transform_exclusive_scan (C++17)
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has_single_bit (C++20)     bit_cast (C++20) bit_ceil (C++20) bit_floor (C++20) bit_width (C++20) rotl (C++20) rotr (C++20)	popcount (C++20) countl_zero (C++20) countl_one (C++20) countr_zero (C++20) countr_one (C++20) byteswap (C++23) endian (C++20)

 

std::complex

Member functions
complex::complex complex::operator= complex::real complex::imag	complex::operator+=complex::operator-=complex::operator*=complex::operator/=
Non-member functions
operator+operator- operator+operator-operator*operator/ operator==operator!= (until C++20)   operator<<operator>> get(std::complex) (C++26)	real imag abs arg norm conj proj (C++11) polar operator""ioperator""ifoperator""il (C++14)(C++14)(C++14)
Exponential functions
log   log10   exp
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pow   sqrt
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sin   cos tan asin (C++11) acos (C++11) atan (C++11)
Hyperbolic functions
sinh   cosh tanh asinh (C++11) acosh (C++11) atanh (C++11)
Helper types
tuple_size<std::complex> (C++26)
tuple_element<std::complex> (C++26)

 

Defined in header <complex>
template< std::size_t I, class T > struct tuple_element<I, std::complex<T>>;		(since C++26)

The partial specializations of std::tuple_element for std::complex provide compile-time access to the underlying real and imaginary number type of a complex, using tuple-like syntax. They are provided for structured binding support. The program is ill-formed if I >= 2.

Member types

Member type	Definition
type	T

Notes

Feature-test macro	Value	Std	Feature
__cpp_lib_tuple_like	202311L	(C++26)	Add tuple protocol to std::complex

Example

Run this code

#include <complex>
#include <type_traits>
 
static_assert([z = std::complex<float>()]
{
    using T = decltype(z);
    return
#if __cpp_lib_tuple_like >= 202311L
        std::is_same_v<std::tuple_element_t<0, T>, float> &&
        std::is_same_v<std::tuple_element_t<1, T>, float> &&
#endif
        std::is_same_v<T::value_type, float>;
}());
 
int main() {}

See also

Structured binding (C++17)	binds the specified names to sub-objects or tuple elements of the initializer
tuple_element (C++11)	obtains the element types of a tuple-like type (class template)
std::tuple_size<std::complex> (C++26)	obtains the size of a std::complex (class template specialization)
get(std::complex) (C++26)	obtains a reference to real or imaginary part from a std::complex (function template)