bbcode v0.1

[bbcode]
[title="Hello World"]
[author="Anonymous"]

[main]
  [let="a"]5[/let]
  [while]a>0[do]
  [let="a"]a-1[/let]
  Hello, World!
  [val="a"]
  [/do]
  [/while]
  [call="test"]
[/main]

[test]
hihihi world!
[/test]

[/bbcode]

suggest and improve.

[definition]
[name]factorial[/name]
[style]function[/style]
[computation]0,0[/computation]
[computation]x,x*[factorial]x-1[/factorial][/computation]
[/definition]

[factorial]4[/factorial]


24