D语言字符

import std.stdio;
import std.uni;

void main() { 
   writeln("Is ğ lowercase? ", isLower('ğ')); 
   writeln("Is Ş lowercase? ", isLower('Ş'));  

   writeln("Is İ uppercase? ", isUpper('İ')); 
   writeln("Is ç uppercase? ", isUpper('ç')); 

   writeln("Is z alphanumeric? ",       isAlpha('z'));  
   writeln("Is new-line whitespace? ",  isWhite('/n')); 

   writeln("Is underline whitespace? ", isWhite('_'));  

   writeln("The lowercase of Ğ: ", toLower('Ğ')); 
   writeln("The lowercase of İ: ", toLower('İ')); 

   writeln("The uppercase of ş: ", toUpper('ş')); 
   writeln("The uppercase of ı: ", toUpper('ı')); 
}