Std::iswlower (3) Linux Manual Page

std::iswlower – std::iswlower

Synopsis

Defined in header<cwctype>

    int iswlower(std::wint_t ch);

Checks if the given wide character is a lowercase letter, i.e. one of abcdefghijklmnopqrstuvwxyz or any lowercase letter 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 lowercase letter, zero otherwise.

Notes

ISO_30112 specifies which Unicode characters are include in POSIX lower category.

Example

// Run this code

#include <iostream>

#include <cwctype>

#include <clocale>
int main()

{
    wchar_t c = L'\u0444'; // Cyrillic small letter ef ('ф')
    std::cout << std::hex << std::showbase << std::boolalpha;
    std::cout << "in the default locale, iswlower(" << (std::wint_t)c << ") = "
              << (bool)std::iswlower(c) << '\n';
    std::setlocale(LC_ALL, "en_US.utf8");
    std::cout << "in Unicode locale, iswlower(" << (std::wint_t)c << ") = "
              << (bool)std::iswlower(c) << '\n';
}

Output:

in the default locale, iswlower(0x444) = false
in Unicode locale, iswlower(0x444) = true

                     checks if a character is classified as lowercase by a locale
islower(std::locale) (function template)
                     checks if a character is lowercase
islower (function)
ASCII values iscntrl isprint isspace isblank isgraph ispunct isalnum isalpha isupper islower isdigit isxdigit
decimal hexadecimal octal characters iswcntrl iswprint iswspace iswblank iswgraph iswpunct iswalnum iswalpha iswupper iswlower iswdigit iswxdigit
0–8 \x0–\x8 \0–\10 control codes (NUL, etc.) ≠0 0 0 0 0 0 0 0 0 0 0 0
9 \x9 \11 tab (\t) ≠0 0 ≠0 ≠0 0 0 0 0 0 0 0 0
10–13 \xA–\xD \12–\15 whitespaces (\n, \v, \f, \r) ≠0 0 ≠0 0 0 0 0 0 0 0 0 0
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–\10ABCDEF 0 ≠0 0 0 ≠0 0 ≠0 ≠0 ≠0 0 0 ≠0
71–90 \x47–\x5A \107–\13GHIJKLMNOP 0 ≠0 0 0 ≠0 0 ≠0 ≠0 ≠0 0 0 0
                              QRSTUVWXYZ
91–96 \x5B–\x60 \133–\14[\]^_` 0 ≠0 0 0 ≠0 ≠0 0 0 0 0 0 0
97–102\x61–\x66 \141–\14abcdef 0 ≠0 0 0 ≠0 0 ≠0 ≠0 0 ≠0 0 ≠0
103–12\x67–\x7A \147–\17ghijklmnop 0 ≠0 0 0 ≠0 0 ≠0 ≠0 0 ≠0 0 0
                              qrstuvwxyz
123–12\x7B–\x7E \172–\17{|}~ 0 ≠0 0 0 ≠0 ≠0 0 0 0 0 0 0
127 \x7F \177 backspace character (DEL) ≠0 0 0 0 0 0 0 0 0 0 0 0

std::iswlower (3) Linux Manual Page