ISO INTERNATIONAL STANDARD 24610-2 First edition 2011-10-01 Language resource management - Feature structures - Part 2: Feature system declaration Gestion des ressources langagieres Structures de traits- Partie 2: Déclaration de systeme de structures de traits Reference number ISO 24610-2:2011(E) @ ISO 2011 IHSunder Not for Resale ISO 24610-2:2011(E) COPYRIGHTPROTECTEDDOCUMENT @ISO2011 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either isO at the address below or isO's memberbody in the country of the requester. ISO copyright office Case postale 56 : CH-1211 Geneva 20 Tel. + 41 22 749 01 11 Fax + 41 22 749 09 47 E-mail [email protected] Web www.iso.org Published in Switzerland @ ISO 2011 - All rights reserved nited without license from IHS Not for Resale ISO 24610-2:2011(E) Contents Page Foreword .iv Introduction 1 Scope 2 Normative references.. 3 Terms and definitions 4 Overall structure .5 5 Basic concepts .... 5.1 Typed feature structures reviewed. 5.2 5.3 Type inheritance hierarchies..... 9 5.4 Type constraints.... 5.5 Optional (default) values and underspecification. 12 5.6 Subsumption... 12 6 Defining well-formedness versus validity... 14 6.1 6.2 ISO24610. 14 A feature system for a grammar... 19 7.1 Overview.... 19 7.2 Sample FSDs.. 8 Declaration of a feature system 23 8.1 Overview.. 24 8.2 Linking a text to feature system declarations .24 8.3 Overall structure of a feature system declaration .25 8.4 Feature declarations .... 8.5 Feature structure constraints .33 Annex A (normative) XML schema for feature structures. .36 Annex B (informative) A complete example... ..46 Bibliography. ii se from IHS Not for Resale