401             carry_len: 0,  in iter()
410     carry_len: usize,  field
428                 if self.carry_len == 3 {  in next()
429                     let out = (self.carry, NUM_CHARS_BITS[self.carry_len]);  in next()
430                     self.carry_len = 0;  in next()
439                     if self.carry_len + new_chars > 3 {  in next()
440                         self.carry_len = new_chars + self.carry_len - 3;  in next()
442                             self.carry * POW10[new_chars - self.carry_len]  in next()
443                                 + bits / POW10[self.carry_len],  in next()
446                         self.carry = bits % POW10[self.carry_len];  in next()
451                             NUM_CHARS_BITS[self.carry_len + new_chars],  in next()
453                         self.carry_len = 0;  in next()
456                 } else if self.carry_len > 0 {  in next()
457                     let out = (self.carry, NUM_CHARS_BITS[self.carry_len]);  in next()
458                     self.carry_len = 0;  in next()