Now tell me what extra information you want to put in the
second models.??? Note that here we??™re asking for information, most likely on a
(problem) domain level, not for the actual representation of that information. ???Now
let??™s look at howwe can extend or change the high-level modeling language to provide
places to capture that information.??? (Sometimes this step may require rethinking the
modeling language, especially if it??™s been based on a language that somebody had
already made.) ???And ?¬?nally, let??™s showhowwe nowhave all the information we need,
and we can generate full code directly from the ?¬?rst model, using the information it
originally captured and the new information we would otherwise have entered in the
second model.??? You should remember that there was only a certain amount of
information to be added to the second lower-level model, regardless of its
INTEGRATING MULTIPLE LANGUAGES 255
representation or duplication into several places there. Since we would earlier have
been able to generate the initial second model from the information in the ?¬?rst highlevel
model, add extra information, and then generate code, we can nowclearly expect
to be able to generate full code straight from the ?¬?rst model.
Summa summarum: if you can specify a transformation from a high-level model to
a second, lower-level model and then have modelers add more detail and perform
another transformation into code, you can look instead at the information that gets
added by modelers, extend the high-level language used to specify the ?¬?rst model to
capture it, and merge the transformations into one.
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