tests/meta.g

   1 // use 'a'-'z' or 'a-z' instead of [a-z]?
   2 // EOF token?
   3 // #include (with renaming?)
   4
   5 s             =  ws! Grammar ws!
   6
   7 Grammar       =  NonTerminal +/ ws
   8
   9 NonTerminal   =  Word           "="     RHS /ws
  10               |  Word  "*" ws! ^"=" ws! RHS
  11               |  Word  "*/" Word ws! ^"=" ws! RHS
  12
  13 RHS           =  (Sequence +/ (ws! "|" ws!)) +/ (ws! ">" ws!)
  14
  15 Elements      =  e*/ws
  16
  17 PreSequence   =  Elements
  18               |  (Quoted|Word)   ^"::" PreSequence /ws
  19               >  PreSequence     ^"/"      e       /ws
  20               |  PreSequence     ^"->"     e       /ws
  21
  22 Sequence      = psx:: PreSequence
  23               |       Sequence ^"&"  Elements /ws
  24               |       Sequence ^"&~" Elements /ws
  25
  26 ec            = ~[\-\]\\]
  27               | escaped
  28
  29 Range         = ec
  30               | ec ^"-" ec
  31
  32 e             =                (Quoted|Word) ^":" e
  33               >                NonTerminalReference
  34               |                Literal
  35               |                  ^"()"
  36               |                  ^"{" PreSequence "}"    /ws
  37               |                  ^"["  Range* "]"
  38               |                e ^"++"                   /ws -> ~[/]
  39               |                e ^"+"                    /ws -> ~[+]
  40               |                e ^"++/" e                /ws
  41               |                e ^"+/"  e                /ws
  42               |                e ^"**"                   /ws -> ~[/]
  43               |                e ^"*"                    /ws -> ~[*]
  44               |                e ^"**/" e                /ws
  45               |                e ^"*/"  e                /ws
  46               |                     e ^"!"
  47               |                e ^"?"                    /ws
  48               |                  ^"^"   Quoted
  49               >                  ^"(" RHS  ")"           /ws
  50               |                  ^"~" e
  51
  52 NonTerminalReference = Word
  53 Literal              = Quoted
  54 Word                 = [a-zA-Z0-9_]++
  55 Quoted               = "\"" ((~[\"\\] | escaped)+) "\""
  56                      | EmptyString
  57                        EmptyString = "\"\""
  58
  59 escaped    = "\n":: "\\n"
  60            | "\r":: "\\r"
  61            |        "\\" ~[nr]
  62
  63 w             = " " | "\n" | "\r"
  64 ws            =  "()":: w**
  65               |  "()":: w** "//" (~[\n])* "\n" ws
  66 wp            =  w++