Rat12F     Function   function  Identifier
  ( )   : : ; , {} = []
    int     boolean    real
  If    if  else  fi while
 Return    return ;   printf   scanf ( IDs ) ;
 ==   !=     >> <   =>    <=       + - *  // -
          true  false
     123   0000    13.456   .567    12.45.67.
    a_c__4t        a____t    x
      x56      _fgt
   % &
   /* Middle */

   /* end
   */
67yu