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       =  Declaration +/ ws
   8
   9 Declaration   =  NonTerminal
  10               |  ^"#import" ws! FileName //(ws! "as" ws! Prefix)?
  11
  12 //Prefix        = ([a-zA-Z] ".")+ "*"
  13 FileName      = FileNameChar+ -> [\r\n ]
  14 FileNameChar  = Space:: "\\ "
  15               | ~[\r\n ]
  16
  17 NonTerminal   =  Word           "="     RHS /ws
  18               |  Word  "*" ws! ^"=" ws! RHS
  19               |  Word  "*/" Word ws! ^"=" ws! RHS
  20
  21 RHS           =  (Sequence +/ (ws! "|" ws!)) +/ (ws! ">" ws!)
  22
  23 Elements      =  e*/ws
  24
  25 PreSequence   =  Elements
  26               |  (Quoted|Word)   ^"::" PreSequence /ws
  27               >  PreSequence     ^"/"      e       /ws
  28               |  PreSequence     ^"->"     e       /ws
  29
  30 Sequence      = psx:: PreSequence
  31               |       Sequence ^"&"  Elements /ws
  32               |       Sequence ^"&~" Elements /ws
  33
  34 ec            = ~[\-\]\\]
  35               | escaped
  36
  37 Range         = ec
  38               | ec ^"-" ec
  39
  40 e             =                (Quoted|Word) ^":" e
  41               >                NonTerminalReference
  42               |                Literal
  43               |                  ^"()"
  44               |                  ^"{" PreSequence "}"    /ws
  45               |                  ^"["  Range* "]"
  46               |                e ^"++"                   /ws -> ~[/]
  47               |                e ^"+"                    /ws -> ~[+]
  48               |                e ^"++/" e                /ws
  49               |                e ^"+/"  e                /ws
  50               |                e ^"**"                   /ws -> ~[/]
  51               |                e ^"*"                    /ws -> ~[*]
  52               |                e ^"**/" e                /ws
  53               |                e ^"*/"  e                /ws
  54               |                     e ^"!"
  55               |                e ^"?"                    /ws
  56               |                  ^"^"   Quoted
  57               >                  ^"(" RHS  ")"           /ws
  58               |                  ^"~" e
  59
  60 NonTerminalReference = Word
  61 Literal              = Quoted
  62 Word                 = [.a-zA-Z0-9_]++
  63 Quoted               = "\"" ((~[\"\\] | escaped)+) "\""
  64                      | EmptyString
  65                        EmptyString = "\"\""
  66
  67 escaped    = "\n":: "\\n"
  68            | "\r":: "\\r"
  69            |        "\\" ~[nr]
  70
  71 w             = " " | "\n" | "\r"
  72 ws            =  "()":: w**
  73               |  "()":: w** "//" (~[\n])* "\n" ws
  74 wp            =  w++