std::iswgraph(3)

🌈 std::iswgraph(3) 🌈

okay so this is the std::iswgraph(3) page from the C++ Standard Libary manual — yes, that's literally how the header spells it, and we're moving on 💀. It's the C++ Standard Library's wide-character graph check, and it's giving "tiny function, big locale energy." 💅

💖 NAME 💖

std::iswgraph — std::iswgraph (the NAME section said what it said, bestie 🫶).

✨ Synopsis ✨

Defined in header <cwctype>:

int iswgraph( std::wint_t ch );

Checks if the given wide character has a graphical representation, i.e. it is either:

• a number (0123456789),
• an uppercase letter (ABCDEFGHIJKLMNOPQRSTUVWXYZ),
• a lowercase letter (abcdefghijklmnopqrstuvwxyz),
• a punctuation character (!"#$%&'()*+,-./:;<=>?@[\]^_`{|}~), or
• any graphical character specific to the current C 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. Like, do not test fate with that one, bestie.

🌸 Parameters 🌸

• ch — wide character.

🎀 Return value 🎀

Non-zero value if the wide character has a graphical representation character, zero otherwise.

🦋 Notes 🦋

ISO 30112 specifies which Unicode characters are include in the POSIX graph category. (That's the note, periodt.)

💅 Example 💅

// Run this code

#include <clocale>
#include <cwctype>
#include <iostream>

int main()
{
    wchar_t c = L'\u2602'; // the Unicode character Umbrella ('☂')

    std::cout << std::hex << std::showbase << std::boolalpha
              << "in the default locale, iswgraph("
              << static_cast<std::wint_t>(c) << ") = "
              << static_cast<bool>(std::iswgraph(c)) << '\n';

    std::setlocale(LC_ALL, "en_US.utf8");
    std::cout << "in Unicode locale, iswgraph("
              << static_cast<std::wint_t>(c) << ") = "
              << static_cast<bool>(std::iswgraph(c)) << '\n';
}

🍓 Output 🍓

in the default locale, iswgraph(0x2602) = false
in Unicode locale, iswgraph(0x2602) = true

👑 See also 👑

• isgraph(std::locale) — checks if a character is classified as graphical by a locale (function template).
• isgraph — checks if a character is a graphical character (function).
• C documentation for iswgraph.

and because we do not skip the iconic data, here's the whole ASCII values table from the page, preserved in all its chaotic glory 🫶:

               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)

mwah 💋 — signing off from http://cppreference.com, stamped 2024.06.10, for std::iswgraph(3). bye bestie! 💖✨