tests/meta.g

   1 s           ::=  !ws Grammar ws              => "gram"
   2 Grammar     ::=  NonTerminal +/ ws           => "grammar"
   3 NonTerminal ::=  word  ^"::=" RHS /ws
   4
   5 RHS         ::=  (Conjuncts +/ (!ws "|" !ws)) +/ (!ws ">" !ws)
   6
   7 Conjuncts   ::=  Sequence
   8               |  Sequence ^"&"  Elements  /ws
   9               |  Sequence ^"&~" Elements  /ws
  10 Elements    ::=  e*/ws
  11 NamedElements    ::=  (e | word ^":" e) */ ws
  12
  13 PreSequence ::= NamedElements => "ps"
  14               | PreSequence !wp ^"/"  !ws e
  15               | PreSequence     ^"->"     e /ws
  16               | PreSequence     ^"=>" ("[]"|"()"|word|Quoted) /ws
  17 Sequence    ::= PreSequence    => "psx"
  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
  31               |  e ^"++"                   /ws -> ~[/]
  32               |  e ^"+"                    /ws -> ~[+]
  33               |  e ^"++/" e                /ws
  34               |  e ^"+/"  e                /ws
  35               |  e ^"**"                   /ws -> ~[/]
  36               |  e ^"*"                    /ws -> ~[*]
  37               |  e ^"**/" e                /ws
  38               |  e ^"*/"  e                /ws
  39               |    ^"!"   e                /ws
  40               |  e ^"?"                    /ws
  41               |    ^"^" Quoted             /ws
  42
  43               |     "(" word         ^")"  /ws
  44               >    ^"(" RHS  ")"           /ws
  45               |    ^"~" e
  46
  47 word     ::= [a-zA-Z0-9_]++
  48 Quoted   ::= "\"" ((~[\"\\] | escaped)+) "\""
  49            | "\"\"" => ""
  50 escaped  ::= "\\n" => "\n"
  51            | "\\r" => "\r"
  52            | "\\" ~[nr]
  53
  54
  55 w           ::= " " | "\n" | "\r"
  56 ws          ::=  w** => ()
  57               |  w** "//" ~[\n]* "\n" ws => ()
  58 wp          ::=  w++