; Header is optional.
;---------------------------------------------------------  ; drawLine() is invalid in Header.
<<<<<<<<<<<<<<<<<|><><><><><><><|===========>&=======<>>>>  ;
 >> MetaChar is [SP]meta[SP] << & >> Comment is [SP]; <<;     This is an exception.
 >< @<b>{center} <><<><><>      & <> cen@<t>{t}er ><>>>>>      ; ## Markdown like #######
----------------------------------------------------------
 0 \> 1          & 0 \>1        & 0\> 1      & 0>1 or 0\>1  ; `0 > 1, 0 >1, 0> 1` is error.
 (^ \_ ^)        & ^            & A _ B      & x^2          ; `x ^ 2` is \backslashbox{x}{2}
 アイハブア    \ & アイハブア \ & I have a \ & I have a \   ; ascii(line1, line2) ?
 ペン            & Pen          & ペン       & Pen.         ;     line1 + [SP] + line2 : line1 + line2
 \textbf{ABCD}   & >>> {\LaTeX}, \\texttt{ABC}, $\sin$ <<<  ; `[SP]\` is error.
 printf();       & ioctl();     & ls; pwd    & ; This is comment.
----------------------------------------------------------
              NOT|SPACE       ab|cdefghijklmn|opqrstu
;---------------------------------------------------------  ; drawLine() is invalid in Last