; () block (1)
; {} repetition block (0, 1, n)
; [] conditional block (0, 1)
; := rule assignment
; ; comment
; | or

Module = Program | Unit | Library | Package
Program = ['program' <Name> ';'] <Unit>
VariableDeclaration = 'var' ( <Name> ':' <Type> ';' )# <Unit>
BeginEnd = 'begin' ( Command )* 'end' ';'
IfThenElse = 'if' Condition 'then' Statement ( 'else' Statement )#