gml_parser.trx

(*
    Copyright © 2011 MLstate

    This file is part of OPA.

    OPA is free software: you can redistribute it and/or modify it under the
    terms of the GNU Affero General Public License, version 3, as published by
    the Free Software Foundation.

    OPA is distributed in the hope that it will be useful, but WITHOUT ANY
    WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
    FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for
    more details.

    You should have received a copy of the GNU Affero General Public License
    along with OPA. If not, see <http://www.gnu.org/licenses/>.
*)
(* A simple GML (Graph Modelling Language) parser
   syntax from http://www.infosun.fim.uni-passau.de/Graphlet/GML/gml-tr.html
*)

types:{{
  type gml = Int of int | Float of float | String of string | List of (string * gml) list
}}

+gml : {gml} <- list {{ List __1 }}
list <- (whitespace* key whitespace+ value whitespace* {{ __2, __4 }})*
value <- Integer {{ Int __1 }}
       / Real {{ Float __1 }}
       / String {{ String __1 }}
       / '[' list ']' {{ List __2 }}

key <- [a-zA-Z][a-zA-Z0-9]* $_
Integer	<- (sign [0-9]+ $_) {{ int_of_string __1 }}
Real <- (sign [0-9]* '.' [0-9]* ( 'E' sign [0-9] ) $_) {{ float_of_string __1 }}
String <- '"' (instring* $_) '"' {{ __2 }}
sign <- ('+' / '-')? $_
instring <- ![&\"] . $_ / '&' [a-zA-Z]+ ';' $_ # html escapes (&nbsp;)
whitespace <- [ \t\n] $ / comment $
comment <- '#' (!EOL .)* (EOL / EOF) $
EOL <- [\n\r] $ / '\r\n' $
EOF <- !.