public function readOne()
    {
        if ($this->pos <= $this->max) {
            $value = $this->string[$this->pos];
            $this->pos += 1;
        } else {
            $value = null;
        }

        return $value;
    }
public function readOne()
    {
        if ($this->pos <= $this->max) {
            $value = $this->string[$this->pos];
            $this->pos += 1;
        } else {
            $value = null;
        }

        return $value;
    }
public function readOne ( ) { if ( $ this -> pos <= $ this -> max ) { $ value = $ this -> string [ $ this -> pos ] ; $ this -> pos += 1 ; } else { $ value = null ; } return $ value ; }
Read the next character from the supplied string.
Return null when we have run out of characters.
Read the next character from the supplied string . Return null when we have run out of characters .