Syntax

1 COMMAND_NAME required_variable
2? 
2 OPTIONAL_KEYWORD=variable
3!  KEYWORD=default_choice
3?
3 KEYWORD=
3.1 choice2
3.1 choice3
4+ 
4 repeatable_item1
5? %fragment_name
6? 
6 optional_choice1
6 optional_choice2
7 required_choice1
7 required_choice2
7 required_choice3
8+ ,
8 repeatable_item2
9! DEFAULT_KEYWORD
9?
9 KEYword

1! DEFAULT_KEYWORD
1?
1 KEYWORD1
1 KEYWORD2
2.0 (
2.0.1+ 
2.0.1 variable1
2.0.2 )
2.0.3! KEYWORD3 KEYWORD4
2.0.3?
2.0.3 variable2 variable3
2 (
2.1+ ,
2.1 variable4  - variable5
2.2 )
2.3? 
2.3 OPTIONAL_KEYWORD1
2.3 OPTIONAL_KEYWORD2
2.3 OPTIONAL_KEYWORD3