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Left: The DATR language Up: The DATR language Right: Lexical tokens


  A DATR description consists of a sequence of sentences corresponding semantically to a set of statements. Sentences are built up out of a small set of basic expression types, built up out of sequences of lexical tokens, which we take to be primitive.

In the previous section, we referred to individual lines in DATR definitions as statements. Syntactically however, a DATR description consists of a sequence of sentences, where each sentence starts with a node name and ends with a period, and contains one or more path equations relating to that node, each corresponding to a statement in DATR. This distinction between sentences and statements is primarily for notational convenience (it would be cumbersome to require repetition of the node name for each statement) and statements are the primary unit of specification in DATR. For the purposes of this section, where we need to be particularly clear about this distinction, we shall call a sentence containing just a single statement a simple sentence.




Copyright © Roger Evans, Gerald Gazdar & Bill Keller, Tuesday 10 November 1998