Simple.bnf

{
  tokens = [
  	crlf='regexp:\n'
  	escaped_crlf='regexp:^\\(\n)'
    comment='regexp:[#|!][^\n]*'
    nonId='regexp:[:=\s\\]'
    sepearator='regexp:\s*(=|:)\s*'
    id='regexp:[^#|!:=\s\n\\]([^:=\s\n\\]|(\\\s))*'
  ]
}

root ::= item*

private item ::= (property|comment|crlf)

property ::= key sepearator value

key ::= id?

value ::= (id|sepearator|nonId|escaped_crlf)*