tests/meta.g

   1 s         ::=  ws grammar ws                  => "gram"
   2 ws       !::=  w**
   3 grammar   ::=  r +/ ws                        => "grammar"
   4 r         ::=  word  ^"::=" alternatives /ws
   5             |  word ^"!::=" alternatives /ws
   6
   7 alternatives  ::=  (conjuncts +/ (ws "|" ws)) +/ (ws ">" ws)
   8
   9 conjuncts   ::=  sequence
  10               |  sequence ^"&"  e*/ws   /ws
  11               |  sequence ^"&~" e*/ws   /ws
  12
  13 ps          ::= e*/ws => "ps"
  14 psx         ::= ps
  15               > ps ^"/" e /ws
  16 sequence    ::= psx
  17               | psx ^"=>" (word|quoted) /ws
  18
  19 ec       ::= [~\-\]\\\~]
  20            | escaped
  21
  22 range    ::= ec          => "range"
  23            | ec ^"-" ec
  24
  25 e        ::=  word                          => "nonTerminal"
  26            |  quoted                        => "literal"
  27            |    ^"()"
  28            |    ^"{" sequence "}"       /ws
  29            |    ^"["  (range*) "]"
  30            |    ^"[~" (range*) "]"
  31            |    ^"^" quoted             /ws
  32            |    ^"!" e                  /ws
  33
  34            |  (e ws ^"**" > e ws ^"*")
  35            |  e ^"*/" e                 /ws
  36            |  (e ws ^"++" > e ws ^"+")
  37            |  e ^"+/" e                 /ws
  38            |  e ^"?"                    /ws
  39
  40            |     "(" word         ^")"  /ws
  41            >    ^"(" alternatives  ")"  /ws
  42
  43 w       !::= " "
  44            | "//" ([~\n]*) "\n"
  45            | "\n"
  46            | "\r"
  47 word     ::= [a-zA-Z0-9_]++
  48 quoted   ::= "\"" (([~\"\\] | escaped)+) "\""
  49            | "\"\"" => ""
  50 escaped  ::= "\\n" => "\n"
  51            | "\\r" => "\r"
  52            | "\\" [~nr]
  53
  54