tests/meta.g

   1 s             =  !ws (grammar::Grammar) !ws
   2
   3 Grammar       =  NonTerminal +/ ws
   4
   5 NonTerminal   =  Word ^"=" RHS /ws
   6
   7 // use 'a'-'z' or 'a-z' instead of [a-z]?
   8 // EOF token?
   9 // #include (with renaming?)
  10 // ANTLR uses ! and ^ suffixes
  11
  12 RHS           =  (Sequence +/ (!ws "|" !ws)) +/ (!ws ">" !ws)
  13
  14 Elements      =  e*/ws
  15
  16 PreSequence   = ps::  Elements
  17               |       (Quoted|Word)   ^"::" PreSequence /ws
  18               >       PreSequence     ^"/"      e       /ws
  19               |       PreSequence     ^"->"     e       /ws
  20
  21 Sequence      = psx:: PreSequence
  22               |       Sequence ^"&"  Elements /ws
  23               |       Sequence ^"&~" Elements /ws
  24
  25 ec            = ~[\-\]\\]
  26               | escaped
  27
  28 Range         = range:: ec
  29               |         ec ^"-" ec
  30
  31 e             =                (Quoted|Word) ^":" e
  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++