D语言continue语句

import std.stdio;

int main () {
   /* local variable definition */
   int a = 10;

   /* do loop execution */
   do {
      if( a == 15) {
         /* skip the iteration */
         a = a + 1;
         continue;
      }
      writefln("value of a: %d", a);
      a++;

   } while( a < 20 );

   return 0;
}