[1]	ebnf	::=	(declaration | rule)*
[2]	declaration	::=	"@terminals" | pass
[3]	rule	::=	LHS expression
[4]	expression	::=	alt
[5]	alt	::=	seq ("|" seq)*
[6]	seq	::=	diff+
[7]	diff	::=	postfix ("-" postfix)?
[8]	postfix	::=	primary POSTFIX?
[9]	primary	::=	HEX | SYMBOL | O_RANGE | RANGE | STRING1 | STRING2 | ("(" expression ")")
[10]	pass	::=	"@pass" expression
@terminals			# Productions for terminals
[11]	LHS	::=	("[" SYMBOL "]" #x20+)? SYMBOL #x20* "::="
[12]	SYMBOL	::=	([a-z] | [A-Z] | [0-9] | "_" | ".")+
[13]	HEX	::=	"#x" ([a-f] | [A-F] | [0-9])+
[14]	RANGE	::=	"[" ((R_CHAR "-" R_CHAR) | (HEX "-" HEX) | R_CHAR | HEX)+ "-"? ("]" - LHS)
[15]	O_RANGE	::=	"[^" ((R_CHAR "-" R_CHAR) | (HEX "-" HEX) | R_CHAR | HEX)+ "-"? "]"
[16]	STRING1	::=	'"' (CHAR - '"')* '"'
[17]	STRING2	::=	"'" (CHAR - "'")* "'"
[18]	CHAR	::=	[#x09#x0A#x0D] | [#x20-#xD7FF] | [#xE000-#xFFFD] | [#x00010000-#x0010FFFF]
[19]	R_CHAR	::=	CHAR - ("]" | "-" | HEX)
[20]	POSTFIX	::=	[?*+]
[21]	PASS	::=	[#x09#x0A#x0D#x20] | ((("#" - "#x") | "//") [^#x0A#x0D]*) | ("/*" (("*" [^/])? | [^*])* "*/") | ("(*" (("*" [^)])? | [^*])* "*)")
@pass			PASS