For modelers, the integrated metamodel gives a fundamental bene?¬?t: They
can see other models, and models update automatically based on changes made
elsewhere. Data in models can then be edited in an integrated way and there is no need
for copying and pasting elements between different models or maintaining references
among models. If the DSM tool supports multiple users, the change can be
simultaneous for all developers. Also, model partitioning and versioning can be
supported by allowing work with models consisting of multiple integrated
speci?¬?cations, rather than versioning small speci?¬?cations separately and externaly
keeping track of their dependencies.
10.5.2 Why Integrating Models with Model-to-Model
Transformation is a Bad Thing
Experiences with model-to-model transformation, whatever tool is involved and
whatever export/transform/import method is used, showthis is normally a Bad Thing.
You should only consider it when you don??™t need to change the automatically
produced model. Let us explain why.
Normally, the idea is that each piece of data in one model gets transformed to more
than one piece of data in the second model (let??™s say two pieces). This is ?¬?ne if you
never (or rarely) look at the second model and never (or very rarely) edit it. But if you
edit it, you are now working with two pieces of data, but clearly they are not totally
254 DSM LANGUAGE DEFINITION
independent, since they could be produced from one piece.
Pages:
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463