tests/meta.g

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