Warning: this is an htmlized version!
The original is across this link,
and the conversion rules are here.
Lua 5.1.5  Copyright (C) 1994-2012 Lua.org, PUC-Rio
> dofile "rect.lua"
> tree = {[0]="+", {[0]="*", "2", "3"}, {[0]="*", "4", "5"}}
> tree = {[0]="+", {[0]="*", "2", "3"}, {[0]="*", "4", "5"}, bar="=", label="hi"}
> = synttorect(tree)
+_____.
|     |
*__.  *__.
|  |  |  |
2  3  4  5
> = dedtorect (tree)
2  3  4  5
----  ----
*     *
=======hi
+
> 
>