;This file follows strict ABNF rules and can be used with abnfgen.


File          = [Unit] *( Blank Unit ) *Blank [Trail]


Unit          = *Blank Datum

Blank         = HTAB / LF / %x0b / %x0c / CR / Comment

Trail         = SkipLine / SkipUnit


Comment       = SkipLine LF / SkipUnit Blank

SkipLine      = ';' [ SkipLStart *AnyButLF ]

SkipUnit      = ';' '~' Unit


SkipLStart    = %x00-09 / %x0b-7d / %x7f-ff
              ; any but LF or '~'

AnyButLF      = %x00-09 / %x0b-ff


Datum         = SingleDatum
              / JoinedDatum *( [ '.' / ':' ] JoinedDatum )


SingleDatum   = BareString / CladDatum / DottedString

JoinedDatum   = BareString / CladDatum


BareString    = BareChar *( BareChar / Numeric )

CladDatum     = '|' *( PipeStrChar / '\' StringEsc ) '|'
              / '"' *( QuotStrChar / '\' StringEsc ) '"'
              / '#' HashExpr
              / '(' List ')' / '[' List ']' / '{' List '}'
              / "'" Datum / '`' Datum / ',' Datum

DottedString  = ( '.' / Numeric ) *( '.' / Numeric / BareChar )


BareChar      = '!' / '$' / '%' / '*' / '/' / '<' / '=' / '>'
              / '?' / '@' / '^' / '_' / '~' / ALPHA

Numeric       = '+' / '-' / DIGIT


PipeStrChar   = %x00-5b / %x5d-7b / %x7d-ff
              ; any but '|' or '\'

QuotStrChar   = %x00-21 / %x23-5b / %x5d-ff
              ; any but '"' or '\'

HashExpr      = Rune [ '\' BareString / CladDatum ]
              / '\' BareString
              / '%' Label ( '%' / '=' Datum )
              / CladDatum

List          = [Unit] *( Blank Unit ) *Blank [Tail] [SkipUnit]

Tail          = '&' Unit *Blank


StringEsc     = '\' / '|' / '"' / *( HTAB / SP ) LF *( HTAB / SP )
              / 'a' / 'b' / 't' / 'n' / 'v' / 'f' / 'r' / 'e'
              / 'x' 1*( 2HEXDIG ) ';'
              / 'u' 1*5HEXDIG ';'
              / 'u' '0' 1*5HEXDIG ';'
              / 'u' '1' '0' 1*4HEXDIG ';'


Rune          = ALPHA *5( ALPHA / DIGIT )

Label         = 1*12( HEXDIG )