checkpoint
[sbp.git] / tests / meta.g
1 s         ::=  ws grammar ws                  => "gram"
2 ws       !::=  w**
3 grammar   ::=  r +/ ws                        => "grammar"
4 r         ::=  word  ^"::=" alternatives /ws
5             |  word ^"!::=" alternatives /ws
6
7 alternatives  ::=  equiAlt   +/ (ws ">" ws)
8 equiAlt       ::=  conjuncts +/ (ws "|" ws)
9
10 conjuncts   ::=  rewrite
11               |  rewrite ^"&"  e*/ws   /ws
12               |  rewrite ^"&~" e*/ws   /ws
13
14 sequence    ::= e */ (w**) (ws "/" e)? => "seq"
15
16 rewrite  ::=  sequence                     /ws => "rewrite"
17            |  sequence ^"=>" (word|quoted) /ws
18
19 ec       ::= [~\-\]\\\~]
20            | escaped
21
22 range    ::= ec          => "range"
23            | ec ^"-" ec
24
25 e        ::= word                             => "nonTerminal"
26            |    [(][)]                        => "epsilon"
27            |    ^"{" alternatives "}"   /ws
28            |    ^"["  (range*) "]"
29            |    ^"[~" (range*) "]"
30            |    ^"^" quoted             /ws
31            |    ^"!" e                  /ws
32
33            |  (e ws ^"**" > e ws ^"*")
34            |  e ^"*/" e                 /ws
35            |  (e ws ^"++" > e ws ^"+")
36            |  e ^"+/" e                 /ws
37            |  e ^"?"                    /ws
38
39            |  quoted                        => "literal"
40
41            |     "(" word ^")"          /ws
42            >    ^"(" alternatives ")"   /ws
43
44 w       !::= " "
45            | "//" ([~\n]*) "\n"
46            | "\n"
47            | "\r"
48 an       ::= [a-zA-Z0-9_]
49 word     ::= an++
50 quoted   ::= "\"" (([~\"\\] | escaped)+) "\""
51            | "\"\"" => ""
52 escaped  ::= "\\n" => "\n"
53            | "\\r" => "\r"
54            | "\\" [~nr]
55
56