std::wcstof, std::wcstod, std::wcstold

`<cwchar>`
`float wcstof( const wchar_t* str, wchar_t** str_end );`		( C++11)
`double wcstod( const wchar_t* str, wchar_t** str_end );`
`long double wcstold( const wchar_t* str, wchar_t** str_end );`		( C++11)

, str.

( std::iswspace), . , . :

. :

()
, ( C) ( )
() e E, ( 10)

. :

()
0x 0X
, ( C) ( )
() p P, ( 2)

. :

()
INF INFINITY

. :

()
NAN NAN( ) NAN. , . NaN .

( C++11)

, C

, str_end, . str_end , .

str		,
str_end

, str . , HUGE_VAL, HUGE_VALF HUGE_VALL. , 0.

#include <cerrno>
#include <clocale>
#include <cwchar>
#include <iostream>
#include <string>

int main()
{
    std::setlocale(LC_ALL, "en_US.utf8");

    const wchar_t* p = L"111.11 -2.22 0X1.BC70A3D70A3D7P+6 -Inf 1.18973e+4932zzz";
    wchar_t* end;
    std::wcout << L" L\"" << p << "\":\n";
    for (double f = std::wcstod(p, &end); p != end; f = std::wcstod(p, &end))
    {
        std::wcout << "  '" << std::wstring(p, end-p) << "' -> ";
        p = end;
        if (errno == ERANGE)
        {
            std::wcout << L" ,  ";
            errno = 0;
        }
        std::wcout << f << '\n';
    }
    
    if (std::setlocale(LC_NUMERIC, "de_DE.utf8"))
    {
        std::wcout << L"  de_DE.utf8:\n";
        std::wcout << L"  '123.45' -> " << std::wcstod(L"123.45", 0) << L'\n';
        std::wcout << L"  '123,45' -> " << std::wcstod(L"123,45", 0) << L'\n';
    }
}

:

 L"111.11 -2.22 0X1.BC70A3D70A3D7P+6 -Inf 1.18973e+4932zzz":
  '111.11' -> 111.11
  ' -2.22' -> -2.22
  ' 0X1.BC70A3D70A3D7P+6' -> 111.11
  ' -Inf' -> -inf
  ' 1.18973e+4932' ->  ,  inf
  de_DE.utf8:
  '123.45' -> 123
  '123,45' -> 123.45

strtofstrtodstrtold	() []
C wcstof







(C++20)

(C++20)
(C++11)





(C++20)


/

(C++11)
(C++11)
(C++11)
(C++17)

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std::wcstof, std::wcstod, std::wcstold