Multi-level description directed generation
David D. McDonald · 1986
The principal deficit of the direct replacement approach is its difficulties with grammar, i.e. the awkwardness of maintaining an adequate representation of the grammatical context or of carrying out grammatically mediated text-level actions such as producing the correct syntactic form for an embedded clause. In other respects, however, the message-directed control flow that drives direct replacement has a great deal to recommend it. Compared with grammar-directed control schemes, message-directed control is more efficient, since every action will contribute to the eventual production of the text. Message-directed control also gives a planner a very clear semantic basis for its communication to the realization component. since the message can be viewed simply as a set of instructions to accomplish specific goals. The question then becomes: is there a way of elaborating the basic, message-directed framework so as to overcome the deficits that plague direct replacement approaches while still keeping the computational properties that have made it attractive?