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open Lexer
type syntree = Term of char list
| NonTerm of char list
| Param of char list
| Opt of syntree
| Rep of syntree
| TermRep of syntree * syntree
| OptRep of syntree
| OrList of syntree list
| Con of syntree * syntree
let analyse str =
let rec rexp s =
let mid = parser [< 'MID >] -> () in
let rec restrexp e1 = parser
[< _ = mid; e2 = andrexp; e = restrexp
(match e1
with OrList l -> OrList (l @ [e2])
| _ -> OrList [e1; e2]
)
>] -> e
| [< >] -> e1
in match s with parser [< e1 = andrexp; e2 = restrexp e1 >] -> e2
and andrexp s =
let rec restand e1 = parser
[< e2 = reprexp; e = restand (Con (e1, e2)) >] -> e
| [< >] -> e1
in match s with parser [< e1 = reprexp; e2 = restand e1 >] -> e2
and reprexp = parser
[< 'LSPAR; e = rexp; 'RSPAR >] -> Opt e
| [< 'PLUS; e = plusexp >] -> e
| [< 'LAPAR; e = rexp; 'RAPAR >] -> OptRep e
| [< e = atom >] -> e
and plusexp = parser
[< 'TERM l; 'LAPAR; e = rexp; 'RAPAR >] -> TermRep (e, Term l)
| [< 'LAPAR; e = rexp; 'RAPAR >] -> Rep e
and atom = parser
[< 'NONTERM l >] -> NonTerm l
| [< 'TERM l >] -> Term l
| [< 'PARAM l >] -> Param l
| [< 'LPAR; e = rexp; 'RPAR >] -> e
in rexp (lexer str)
|