table of contents
std::iswalpha(3) | C++ Standard Libary | std::iswalpha(3) |
NAME¶
std::iswalpha - std::iswalpha
Synopsis¶
Defined in header <cwctype>
int iswalpha( std::wint_t ch );
Checks if the given wide character is an alphabetic character, i.e. either an
uppercase letter (ABCDEFGHIJKLMNOPQRSTUVWXYZ), a lowercase letter
(abcdefghijklmnopqrstuvwxyz) or any alphabetic character specific to the
current
locale.
If the value of ch is neither representable as a wchar_t nor equal to the
value of
the macro WEOF, the behavior is undefined.
Parameters¶
ch - wide character
Return value¶
Non-zero value if the wide character is an alphabetic character, 0 otherwise.
Notes¶
ISO 30112 specifies which Unicode characters are include in POSIX alpha category.
Example¶
// Run this code
#include <clocale>
#include <cwctype>
#include <iostream>
int main()
{
wchar_t c = L'\u0b83'; // Tamil sign Visarga ('ஃ')
std::cout << std::hex << std::showbase << std::boolalpha;
std::cout << "in the default locale, iswalpha(" <<
(std::wint_t)c << ") = "
<< (bool)std::iswalpha(c) << '\n';
std::setlocale(LC_ALL, "en_US.utf8");
std::cout << "in Unicode locale, iswalpha(" <<
(std::wint_t)c << ") = "
<< (bool)std::iswalpha(c) << '\n';
}
Possible output:¶
in the default locale, iswalpha(0xb83) = false
in Unicode locale, iswalpha(0xb83) = true
See also¶
isalpha(std::locale) checks if a character is classified as
alphabetic by a locale
(function template)
isalpha checks if a character is alphabetic
(function)
C documentation for
iswalpha
ASCII values characters iscntrl isprint isspace isblank isgraph ispunct
isalnum isalpha isupper islower isdigit isxdigit decimal hexadecimal octal
iswcntrl iswprint iswspace iswblank iswgraph iswpunct iswalnum iswalpha
iswupper iswlower iswdigit iswxdigit 0–8 \x0–\x8 \0–\10
control codes ≠0 0 0 0 0 0 0 0 0 0 0 0
(NUL, etc.) 9 \x9 \11 tab (\t) ≠0 0 ≠0 ≠0 0 0 0 0 0 0 0
0
whitespaces 10–13 \xA–\xD \12–\15 (\n, \v, \f, ≠0
0 ≠0 0 0 0 0 0 0 0 0 0
\r) 14–31 \xE–\x1F \16–\37 control codes ≠0 0 0 0
0 0 0 0 0 0 0 0 32 \x20 \40 space 0 ≠0 ≠0 ≠0 0 0 0 0 0
0 0 0 33–47 \x21–\x2F \41–\57 !"#$%&'()*+,-./
0 ≠0 0 0 ≠0 ≠0 0 0 0 0 0 0 48–57
\x30–\x39 \60–\71 0123456789 0 ≠0 0 0 ≠0 0
≠0 0 0 0 ≠0 ≠0 58–64 \x3A–\x40
\72–\100 :;<=>?@ 0 ≠0 0 0 ≠0 ≠0 0 0 0 0 0
0 65–70 \x41–\x46 \101–\106 ABCDEF 0 ≠0 0 0
≠0 0 ≠0 ≠0 ≠0 0 0 ≠0 71–90
\x47–\x5A \107–\132 GHIJKLMNOP 0 ≠0 0 0 ≠0 0
≠0 ≠0 ≠0 0 0 0
QRSTUVWXYZ 91–96 \x5B–\x60 \133–\140 [\]^_` 0 ≠0
0 0 ≠0 ≠0 0 0 0 0 0 0 97–102 \x61–\x66
\141–\146 abcdef 0 ≠0 0 0 ≠0 0 ≠0 ≠0 0
≠0 0 ≠0 103–122 \x67–\x7A \147–\172
ghijklmnop 0 ≠0 0 0 ≠0 0 ≠0 ≠0 0 ≠0 0 0
qrstuvwxyz 123–126 \x7B–\x7E \172–\176 {|}~ 0 ≠0
0 0 ≠0 ≠0 0 0 0 0 0 0 127 \x7F \177 backspace ≠0 0 0 0
0 0 0 0 0 0 0 0
character (DEL)
2024.06.10 | http://cppreference.com |