I am translating a project from Lua to C++. In the Lua version, I use Lua's regular expressions, but for a purpose so simple that in C++ I could do it by simply comparing the characters against some Ascii codes.
To do that, however, I need the exact ascii code which each character class matches.
As an example, %s matches all space characters, but what exactly are those characters? I need to know it for every Lua character class.
Take a peek at the Lua source:
case 'a' : res = isalpha(c); break;
case 'c' : res = iscntrl(c); break;
case 'd' : res = isdigit(c); break;
case 'g' : res = isgraph(c); break;
case 'l' : res = islower(c); break;
case 'p' : res = ispunct(c); break;
case 's' : res = isspace(c); break;
case 'u' : res = isupper(c); break;
case 'w' : res = isalnum(c); break;
case 'x' : res = isxdigit(c); break;
case 'z' : res = (c == 0); break; /* deprecated option */
You can see that there are analogous methods in C++ <cctype> (ctype.h):
isalnum Check if character is alphanumeric (function )
isalpha Check if character is alphabetic (function )
isblank Check if character is blank (function )
iscntrl Check if character is a control character (function )
isdigit Check if character is decimal digit (function )
isgraph Check if character has graphical representation (function )
islower Check if character is lowercase letter (function )
isprint Check if character is printable (function )
ispunct Check if character is a punctuation character (function )
isspace Check if character is a white-space (function )
isupper Check if character is uppercase letter (function )
isxdigit Check if character is hexadecimal digit (function )
There are also corresponding ASCII value ranges on that page.