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  • noun A CAT for 'Multi-User Dungeon Definition Language', serendipitously punning on MDL, the language in which 'Zork' was written. MUDDL is the definition language of MUD1. It was designed by Roy Trubshaw with hacked-on additions by Richard Bartle, and is based on the data file used in 'Advent' (the first adventure game of any kind, SUA or MUA - it gave its name to the genre). MUDDL is more general, however, able to cope with direct and indirect objects, and extended to have limited function-calling abilities and parameterisation. It has only a single-level class hierarchy, though, so lines are often repeated, identical but for the name of the objects affected. A database is defined by a set of sections, namely rooms, vocabulary, classes, actions, demons, objects, the travel table and the text used for output. Much of the work is hard-coded into the interpreter rather than lying in MUDDL itself, so changing basic operations is difficult. Deep, limiting distinctions are made between objects, rooms, mobiles, players and containers. All on-the-fly text generation has to be hard-coded, and the language is interpreted asynchronously so any changes are always messy to make.

    That said, a surprisingly large amount can be done with MUDDL - much more than in many of its immediate descendents in other MUAs. Indeed, by adding mainly features (sense 2) that are showpieces of the language's abilities, the impression is conveyed that MUDDL has more up its sleeve than it really does; a tolerant, but basically stupid parser completes the system. The limitations of MUDDL were well known to Trubshaw when he designed it, but he never had the time to do the rewrite he was hoping for having got the rest of the system working (this was left to Bartle, with MUDDLE in 1984). Many MUDDL databases were written by students at Essex University, the most well-known being 'Mist', 'Rock', 'Blud' and 'Uni'; although vastly inferior to MUDDLE, it can be seen that MUDDL was nevertheless quite versatile! See action for an example of a MUDDL definition.

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23rd September 1999: muddl.htm