'Remove whitespace at the beginning or end of line. Also remove
\ at end of line'

def process_line(self, line):

    line = RE_COMMENT.split(line)[0]
    line = line.strip()
    if line.endswith('\\\\'):
        line = line.rstrip('\\\\')
    else:
        raise core.InconsistentTableError('Lines    in    LaTeX    table    have    to    end    with    \\\\')
    return line
