tests/meta.g

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