-s ::= Grammar ws => "gram"
-Grammar ::= NonTerminal +/ ws => "grammar"
-NonTerminal ::= word ^"::=" RHS /ws
-
-w ::= " " | "\n" | "\r"
-ws ::= w** => ()
- | w** "//" (~[\n]*) "\n" ws => ()
-wp ::= w++
-
-RHS ::= (Conjuncts +/ (!ws "|" !ws)) +/ (!ws ">" !ws)
-
-Conjuncts ::= Sequence
- | Sequence ^"&" e*/ws /ws
- | Sequence ^"&~" e*/ws /ws
-
-ps ::= e*/ws => "ps"
- | (e+/ws !ws)? ^"^" Quoted (!ws e+/ws)?
-psy ::= ps
- | ps !wp ^"/" !ws e
-psx ::= psy => "psy"
- | psy ^"->" e /ws
-Sequence ::= Quoted => "qprod"
- > psx => "psx"
- | psx "=>" ^"[]" /ws
- | psx ^"=>" ("()"|word|Quoted) /ws
-
-ec ::= ~[\-\]\\]
- | escaped
-
-Range ::= ec => "range"
- | ec ^"-" ec
-
-e ::= word => "nonTerminal"
- | Quoted => "literal"
- | ^"()"
- | ^"{" Sequence "}" /ws
- | ^"[" Range* "]"
-
- | (e ^"++" /ws > e ^"+" /ws)
- | (e ^"++/" e /ws > e ^"+/" e /ws)
- | (e ^"**" /ws > e ^"*" /ws)
- | (e ^"**/" e /ws > e ^"*/" e /ws)
- | ^"!" e /ws
- | e ^"?" /ws
-
- | "(" word ^")" /ws
- > ^"(" RHS ")" /ws
- | ^"~" e
-
-word ::= [a-zA-Z0-9_]++
-Quoted ::= "\"" ((~[\"\\] | escaped)+) "\""
- | "\"\"" => ""
-escaped ::= "\\n" => "\n"
- | "\\r" => "\r"
- | "\\" ~[nr]
-
-
+s = gram:: !ws Grammar ws
+Grammar = grammar:: NonTerminal +/ ws
+NonTerminal = word !wp ^"=" !wp RHS
+
+RHS = (Conjuncts +/ (!ws "|" !ws)) +/ (!ws ">" !ws)
+
+Conjuncts = Sequence
+ | Sequence ^"&" Elements /ws
+ | Sequence ^"&~" Elements /ws
+Elements = e*/ws
+
+PreSequence = ps:: Elements
+ | PreSequence !wp ^"/" !ws e
+ | PreSequence ^"->" e /ws
+ | (Quoted|word) ^"::" PreSequence /ws
+Sequence = psx:: PreSequence
+
+ec = ~[\-\]\\]
+ | escaped
+
+Range = range:: ec
+ | ec ^"-" ec
+
+e = (Quoted|word) ^":" e
+ > nonTerminal:: word
+ | literal:: Quoted
+ | ^"()"
+ | ^"{" Sequence "}" /ws
+ | ^"[" Range* "]"
+ | e ^"++" /ws -> ~[/]
+ | e ^"+" /ws -> ~[+]
+ | e ^"++/" e /ws
+ | e ^"+/" e /ws
+ | e ^"**" /ws -> ~[/]
+ | e ^"*" /ws -> ~[*]
+ | e ^"**/" e /ws
+ | e ^"*/" e /ws
+ | ^"!" e /ws
+ | e ^"?" /ws
+ | ^"^" Quoted
+ | "(" word ^")" /ws
+ > ^"(" RHS ")" /ws
+ | ^"~" e
+ > "^^":: "^" e
+
+word = [a-zA-Z0-9_]++
+Quoted = "\"" ((~[\"\\] | escaped)+) "\""
+ | "":: "\"\""
+escaped = "\n":: "\\n"
+ | "\r":: "\\r"
+ | "\\" ~[nr]
+
+
+w = " " | "\n" | "\r"
+ws = "()":: w**
+ | "()":: w** "//" ~[\n]* "\n" ws
+wp = w++