-s = ws gram:Grammar ws
-Grammar = grammar:: NonTerminal +/ ws
-NonTerminal = word !wp ^"=" !wp RHS
-
-RHS = (Sequence +/ (!ws "|" !ws)) +/ (!ws ">" !ws)
+// use 'a'-'z' or 'a-z' instead of [a-z]?
+// EOF token?
+// #include (with renaming?)
+
+s = ws! Grammar ws!
+
+Grammar = Declaration +/ ws
+
+Declaration = NonTerminal
+ | ^"#import" ws! FileName (ws! "as" ws! Word)?
+
+FileName = FileNameChar+ -> [\r\n ]
+FileNameChar = Space:: "\\ "
+ | ~[\r\n ]
+
+NonTerminal = Word "=" RHS /ws
+ | Word "*" ws! ^"=" ws! RHS
+ | Word "*/" Word ws! ^"=" ws! RHS
+
+RHS = (Sequence +/ (ws! "|" ws!)) +/ (ws! ">" ws!)
Elements = e*/ws
-PreSequence = ps:: Elements
- | PreSequence !wp ^"/" !ws e
- | PreSequence ^"->" e /ws
- | (Quoted|word) ^"::" PreSequence /ws
+PreSequence = Elements
+ | (Quoted|Word) ^"::" PreSequence /ws
+ > PreSequence ^"/" e /ws
+ | PreSequence ^"->" e /ws
Sequence = psx:: PreSequence
- | Sequence !ws ^"&" !ws Elements
- | Sequence !ws ^"&~" !ws Elements
+ | Sequence ^"&" Elements /ws
+ | Sequence ^"&~" Elements /ws
ec = ~[\-\]\\]
| escaped
-Range = range:: ec
- | ec ^"-" ec
+Range = ec
+ | ec "-" ec
-e = (Quoted|word) ^":" e
- > nonTerminal:: word
- | literal:: Quoted
+e = (Quoted|Word) ^":" e
+ > NonTerminalReference
+ | Literal
| ^"()"
- | ^"{" Sequence "}" /ws
+ | ^"{" PreSequence "}" /ws
| ^"[" Range* "]"
| e ^"++" /ws -> ~[/]
| e ^"+" /ws -> ~[+]
| e ^"*" /ws -> ~[*]
| e ^"**/" e /ws
| e ^"*/" e /ws
- | ^"!" e /ws
+ | e ^"!"
| e ^"?" /ws
| ^"^" Quoted
- | "(" word ^")" /ws
> ^"(" RHS ")" /ws
| ^"~" e
- > "^^":: "^" e
-word = [a-zA-Z0-9_]++
-Quoted = "\"" ((~[\"\\] | escaped)+) "\""
- | "":: "\"\""
+NonTerminalReference = Word
+Literal = Quoted
+Word = [.a-zA-Z0-9_]++
+Quoted = "\"" ((~[\"\\] | escaped)+) "\""
+ | EmptyString
+ EmptyString = "\"\""
+
escaped = "\n":: "\\n"
| "\r":: "\\r"
| "\\" ~[nr]
-
w = " " | "\n" | "\r"
ws = "()":: w**
- | "()":: w** "//" ~[\n]* "\n" ws
+ | "()":: w** "//" (~[\n])* "\n" ws
wp = w++